Historical interpretations of John have been subject to considerable change over the years. Medieval chroniclers provided the first contemporary, or near contemporary, histories of John's reign. One group of chroniclers wrote early in John's life, or around the time of his accession, including Richard of Devizes, William of Newburgh, Roger of Hoveden and Ralph de Diceto. These historians were generally unsympathetic to John's behaviour under Richard's rule, but slightly more positive towards the very earliest years of John's reign. Reliable accounts of the middle and later parts of John's reign are more limited, with Gervase of Canterbury and Ralph of Coggeshall writing the main accounts; neither of them were positive about John's performance as king. Much of John's later, negative reputation was established by two chroniclers writing after the king's death, Roger of Wendover and Matthew Paris, the latter claiming that John attempted conversion to Islam in exchange for military aid from the Almohad ruler Muhammad al-Nasir - a story which is considered to be untrue by modern historians.


Popular representations of John first began to emerge during the Tudor period, mirroring the revisionist histories of the time. The anonymous play The Troublesome Reign of King John portrayed the king as a "proto-Protestant martyr", similar to that shown in John Bale's morality play Kynge Johan, in which John attempts to save England from the "evil agents of the Roman Church". By contrast, Shakespeare's King John, a relatively anti-Catholic play that draws on The Troublesome Reign for its source material, offers a more "balanced, dual view of a complex monarch as both a proto-Protestant victim of Rome's machinations and as a weak, selfishly motivated ruler". Anthony Munday's play The Downfall and The Death of Robert Earl of Huntington portrays many of John's negative traits, but adopts a positive interpretation of the king's stand against the Roman Catholic Church, in line with the contemporary views of the Tudor monarchs. By the middle of the 17th century, plays such as Robert Davenport's King John and Matilda, although based largely on the earlier Elizabethan works, were transferring the role of Protestant champion to the barons and focusing more on the tyrannical aspects of John's behaviour.


Contemporary chroniclers were mostly critical of John's performance as king, and his reign has since been the subject of significant debate and periodic revision by historians from the 16th century onwards. Historian Jim Bradbury has summarised the contemporary historical opinion of John's positive qualities, observing that John is today usually considered a "hard-working administrator, an able man, an able general". Nonetheless, modern historians agree that he also had many faults as king, including what historian Ralph Turner describes as "distasteful, even dangerous personality traits", such as pettiness, spitefulness and cruelty. These negative qualities provided extensive material for fiction writers in the Victorian era, and John remains a recurring character within Western popular culture, primarily as a villain in films and stories depicting the Robin Hood legends.


Henry II wanted to secure the southern borders of Aquitaine and decided to betroth his youngest son to Alais, the daughter and heiress of Humbert III of Savoy. As part of this agreement John was promised the future inheritance of Savoy, Piedmont, Maurienne, and the other possessions of Count Humbert. For his part in the potential marriage alliance, Henry II transferred the castles of Chinon, Loudun and Mirebeau into John's name; as John was only five years old his father would continue to control them for practical purposes. Henry the Young King was unimpressed by this; although he had yet to be granted control of any castles in his new kingdom, these were effectively his future property and had been given away without consultation. Alais made the trip over the Alps and joined Henry II's court, but she died before marrying John, which left the prince once again without an inheritance.


For the remaining years of Richard's reign, John supported his brother on the continent, apparently loyally. Richard's policy on the continent was to attempt to regain through steady, limited campaigns the castles he had lost to Philip II whilst on crusade. He allied himself with the leaders of Flanders, Boulogne and the Holy Roman Empire to apply pressure on Philip from Germany. In 1195 John successfully conducted a sudden attack and siege of Évreux castle, and subsequently managed the defences of Normandy against Philip. The following year, John seized the town of Gamaches and led a raiding party within 50 miles (80 km) of Paris, capturing the Bishop of Beauvais. In return for this service, Richard withdrew his malevolentia (ill-will) towards John, restored him to the county of Gloucestershire and made him again the Count of Mortain.


Unfortunately, Isabella was already engaged to Hugh of Lusignan, an important member of a key Poitou noble family and brother of Count Raoul of Eu, who possessed lands along the sensitive eastern Normandy border. Just as John stood to benefit strategically from marrying Isabella, so the marriage threatened the interests of the Lusignans, whose own lands currently provided the key route for royal goods and troops across Aquitaine. Rather than negotiating some form of compensation, John treated Hugh "with contempt"; this resulted in a Lusignan uprising that was promptly crushed by John, who also intervened to suppress Raoul in Normandy.


In late 1203, John attempted to relieve Château Gaillard, which although besieged by Philip was guarding the eastern flank of Normandy. John attempted a synchronised operation involving land-based and water-borne forces, considered by most historians today to have been imaginative in conception, but overly complex for forces of the period to have carried out successfully. John's relief operation was blocked by Philip's forces, and John turned back to Brittany in an attempt to draw Philip away from eastern Normandy. John successfully devastated much of Brittany, but did not deflect Philip's main thrust into the east of Normandy. Opinions vary amongst historians as to the military skill shown by John during this campaign, with most recent historians arguing that his performance was passable, although not impressive.[nb 8] John's situation began to deteriorate rapidly. The eastern border region of Normandy had been extensively cultivated by Philip and his predecessors for several years, whilst Angevin authority in the south had been undermined by Richard's giving away of various key castles some years before. His use of routier mercenaries in the central regions had rapidly eaten away his remaining support in this area too, which set the stage for a sudden collapse of Angevin power.[nb 9] John retreated back across the Channel in December, sending orders for the establishment of a fresh defensive line to the west of Chateau Gaillard. In March 1204, Gaillard fell. John's mother Eleanor died the following month. This was not just a personal blow for John, but threatened to unravel the widespread Angevin alliances across the far south of France. Philip moved south around the new defensive line and struck upwards at the heart of the Duchy, now facing little resistance. By August, Philip had taken Normandy and advanced south to occupy Anjou and Poitou as well. John's only remaining possession on the Continent was now the Duchy of Aquitaine.


The result was a sequence of innovative but unpopular financial measures.[nb 10] John levied scutage payments eleven times in his seventeen years as king, as compared to eleven times in total during the reign of the preceding three monarchs. In many cases these were levied in the absence of any actual military campaign, which ran counter to the original idea that scutage was an alternative to actual military service. John maximised his right to demand relief payments when estates and castles were inherited, sometimes charging enormous sums, beyond barons' abilities to pay. Building on the successful sale of sheriff appointments in 1194, John initiated a new round of appointments, with the new incumbents making back their investment through increased fines and penalties, particularly in the forests. Another innovation of Richard's, increased charges levied on widows who wished to remain single, was expanded under John. John continued to sell charters for new towns, including the planned town of Liverpool, and charters were sold for markets across the kingdom and in Gascony.[nb 11] The king introduced new taxes and extended existing ones. The Jews, who held a vulnerable position in medieval England, protected only by the king, were subject to huge taxes; £44,000 was extracted from the community by the tallage of 1210; much of it was passed on to the Christian debtors of Jewish moneylenders.[nb 12] John created a new tax on income and movable goods in 1207 – effectively a version of a modern income tax – that produced £60,000; he created a new set of import and export duties payable directly to the crown. John found that these measures enabled him to raise further resources through the confiscation of the lands of barons who could not pay or refused to pay.


John's personal life greatly affected his reign. Contemporary chroniclers state that John was sinfully lustful and lacking in piety. It was common for kings and nobles of the period to keep mistresses, but chroniclers complained that John's mistresses were married noblewomen, which was considered unacceptable. John had at least five children with mistresses during his first marriage to Isabelle of Gloucester, and two of those mistresses are known to have been noblewomen. John's behaviour after his second marriage to Isabella of Angoulême is less clear, however. None of John's known illegitimate children were born after he remarried, and there is no actual documentary proof of adultery after that point, although John certainly had female friends amongst the court throughout the period. The specific accusations made against John during the baronial revolts are now generally considered to have been invented for the purposes of justifying the revolt; nonetheless, most of John's contemporaries seem to have held a poor opinion of his sexual behaviour.[nb 14]


John had already begun to improve his Channel forces before the loss of Normandy and he rapidly built up further maritime capabilities after its collapse. Most of these ships were placed along the Cinque Ports, but Portsmouth was also enlarged. By the end of 1204 he had around 50 large galleys available; another 54 vessels were built between 1209 and 1212. William of Wrotham was appointed "keeper of the galleys", effectively John's chief admiral. Wrotham was responsible for fusing John's galleys, the ships of the Cinque Ports and pressed merchant vessels into a single operational fleet. John adopted recent improvements in ship design, including new large transport ships called buisses and removable forecastles for use in combat.


Royal power in Wales was unevenly applied, with the country divided between the marcher lords along the borders, royal territories in Pembrokeshire and the more independent native Welsh lords of North Wales. John took a close interest in Wales and knew the country well, visiting every year between 1204 and 1211 and marrying his illegitimate daughter, Joan, to the Welsh prince Llywelyn the Great. The king used the marcher lords and the native Welsh to increase his own territory and power, striking a sequence of increasingly precise deals backed by royal military power with the Welsh rulers. A major royal expedition to enforce these agreements occurred in 1211, after Llywelyn attempted to exploit the instability caused by the removal of William de Braose, through the Welsh uprising of 1211. John's invasion, striking into the Welsh heartlands, was a military success. Llywelyn came to terms that included an expansion of John's power across much of Wales, albeit only temporarily.


Innocent gave some dispensations as the crisis progressed. Monastic communities were allowed to celebrate Mass in private from 1209 onwards, and late in 1212 the Holy Viaticum for the dying was authorised. The rules on burials and lay access to churches appear to have been steadily circumvented, at least unofficially. Although the interdict was a burden to much of the population, it did not result in rebellion against John. By 1213, though, John was increasingly worried about the threat of French invasion. Some contemporary chroniclers suggested that in January Philip II of France had been charged with deposing John on behalf of the papacy, although it appears that Innocent merely prepared secret letters in case Innocent needed to claim the credit if Philip did successfully invade England.


Within a few months of John's return, rebel barons in the north and east of England were organising resistance to his rule. John held a council in London in January 1215 to discuss potential reforms and sponsored discussions in Oxford between his agents and the rebels during the spring. John appears to have been playing for time until Pope Innocent III could send letters giving him explicit papal support. This was particularly important for John, as a way of pressuring the barons but also as a way of controlling Stephen Langton, the Archbishop of Canterbury. In the meantime, John began to recruit fresh mercenary forces from Poitou, although some were later sent back to avoid giving the impression that the king was escalating the conflict. John announced his intent to become a crusader, a move which gave him additional political protection under church law.


John's campaign started well. In November John retook Rochester Castle from rebel baron William d'Aubigny in a sophisticated assault. One chronicler had not seen "a siege so hard pressed or so strongly resisted", whilst historian Reginald Brown describes it as "one of the greatest [siege] operations in England up to that time". Having regained the south-east John split his forces, sending William Longespée to retake the north side of London and East Anglia, whilst John himself headed north via Nottingham to attack the estates of the northern barons. Both operations were successful and the majority of the remaining rebels were pinned down in London. In January 1216 John marched against Alexander II of Scotland, who had allied himself with the rebel cause. John took back Alexander's possessions in northern England in a rapid campaign and pushed up towards Edinburgh over a ten-day period.


John's illness grew worse and by the time he reached Newark Castle he was unable to travel any farther; John died on the night of 18 October. Numerous – probably fictitious – accounts circulated soon after his death that he had been killed by poisoned ale, poisoned plums or a "surfeit of peaches". His body was escorted south by a company of mercenaries and he was buried in Worcester Cathedral in front of the altar of St Wulfstan. A new sarcophagus with an effigy was made for him in 1232, in which his remains now rest.


By the Victorian period in the 19th century historians were more inclined to draw on the judgements of the chroniclers and to focus on John's moral personality. Kate Norgate, for example, argued that John's downfall had been due not to his failure in war or strategy, but due to his "almost superhuman wickedness", whilst James Ramsay blamed John's family background and his cruel personality for his downfall. Historians in the "Whiggish" tradition, focusing on documents such as the Domesday Book and Magna Carta, trace a progressive and universalist course of political and economic development in England over the medieval period. These historians were often inclined to see John's reign, and his signing of Magna Carta in particular, as a positive step in the constitutional development of England, despite the flaws of the king himself. Winston Churchill, for example, argued that "[w]hen the long tally is added, it will be seen that the British nation and the English-speaking world owe far more to the vices of John than to the labours of virtuous sovereigns".


John (24 December 1166 – 19 October 1216), also known as John Lackland (Norman French: Johan sanz Terre), was King of England from 6 April 1199 until his death in 1216. John lost the duchy of Normandy to King Philip II of France, which resulted in the collapse of most of the Angevin Empire and contributed to the subsequent growth in power of the Capetian dynasty during the 13th century. The baronial revolt at the end of John's reign led to the sealing of the Magna Carta, a document sometimes considered to be an early step in the evolution of the constitution of the United Kingdom.


Shortly after his birth, John was passed from Eleanor into the care of a wet nurse, a traditional practice for medieval noble families. Eleanor then left for Poitiers, the capital of Aquitaine, and sent John and his sister Joan north to Fontevrault Abbey. This may have been done with the aim of steering her youngest son, with no obvious inheritance, towards a future ecclesiastical career. Eleanor spent the next few years conspiring against her husband Henry and neither parent played a part in John's very early life. John was probably, like his brothers, assigned a magister whilst he was at Fontevrault, a teacher charged with his early education and with managing the servants of his immediate household; John was later taught by Ranulph Glanville, a leading English administrator. John spent some time as a member of the household of his eldest living brother Henry the Young King, where he probably received instruction in hunting and military skills.


John had spent the conflict travelling alongside his father, and was given widespread possessions across the Angevin empire as part of the Montlouis settlement; from then onwards, most observers regarded John as Henry II's favourite child, although he was the furthest removed in terms of the royal succession. Henry II began to find more lands for John, mostly at various nobles' expense. In 1175 he appropriated the estates of the late Earl of Cornwall and gave them to John. The following year, Henry disinherited the sisters of Isabelle of Gloucester, contrary to legal custom, and betrothed John to the now extremely wealthy Isabelle. In 1177, at the Council of Oxford, Henry dismissed William FitzAldelm as the Lord of Ireland and replaced him with the ten-year-old John.


When John's elder brother Richard became king in September 1189, he had already declared his intention of joining the Third Crusade. Richard set about raising the huge sums of money required for this expedition through the sale of lands, titles and appointments, and attempted to ensure that he would not face a revolt while away from his empire. John was made Count of Mortain, was married to the wealthy Isabel of Gloucester, and was given valuable lands in Lancaster and the counties of Cornwall, Derby, Devon, Dorset, Nottingham and Somerset, all with the aim of buying his loyalty to Richard whilst the king was on crusade. Richard retained royal control of key castles in these counties, thereby preventing John from accumulating too much military and political power, and, for the time being, the king named the four-year-old Arthur of Brittany as the heir to the throne. In return, John promised not to visit England for the next three years, thereby in theory giving Richard adequate time to conduct a successful crusade and return from the Levant without fear of John seizing power. Richard left political authority in England – the post of justiciar – jointly in the hands of Bishop Hugh de Puiset and William Mandeville, and made William Longchamp, the Bishop of Ely, his chancellor. Mandeville immediately died, and Longchamp took over as joint justiciar with Puiset, which would prove to be a less than satisfactory partnership. Eleanor, the queen mother, convinced Richard to allow John into England in his absence.


Warfare in Normandy at the time was shaped by the defensive potential of castles and the increasing costs of conducting campaigns. The Norman frontiers had limited natural defences but were heavily reinforced with castles, such as Château Gaillard, at strategic points, built and maintained at considerable expense. It was difficult for a commander to advance far into fresh territory without having secured his lines of communication by capturing these fortifications, which slowed the progress of any attack. Armies of the period could be formed from either feudal or mercenary forces. Feudal levies could only be raised for a fixed length of time before they returned home, forcing an end to a campaign; mercenary forces, often called Brabançons after the Duchy of Brabant but actually recruited from across northern Europe, could operate all year long and provide a commander with more strategic options to pursue a campaign, but cost much more than equivalent feudal forces. As a result, commanders of the period were increasingly drawing on larger numbers of mercenaries.


John initially adopted a defensive posture similar to that of 1199: avoiding open battle and carefully defending his key castles. John's operations became more chaotic as the campaign progressed, and Philip began to make steady progress in the east. John became aware in July that Arthur's forces were threatening his mother, Eleanor, at Mirebeau Castle. Accompanied by William de Roches, his seneschal in Anjou, he swung his mercenary army rapidly south to protect her. His forces caught Arthur by surprise and captured the entire rebel leadership at the battle of Mirebeau. With his southern flank weakening, Philip was forced to withdraw in the east and turn south himself to contain John's army.


John inherited a sophisticated system of administration in England, with a range of royal agents answering to the Royal Household: the Chancery kept written records and communications; the Treasury and the Exchequer dealt with income and expenditure respectively; and various judges were deployed to deliver justice around the kingdom. Thanks to the efforts of men like Hubert Walter, this trend towards improved record keeping continued into his reign. Like previous kings, John managed a peripatetic court that travelled around the kingdom, dealing with both local and national matters as he went. John was very active in the administration of England and was involved in every aspect of government. In part he was following in the tradition of Henry I and Henry II, but by the 13th century the volume of administrative work had greatly increased, which put much more pressure on a king who wished to rule in this style. John was in England for much longer periods than his predecessors, which made his rule more personal than that of previous kings, particularly in previously ignored areas such as the north.


John's royal household was based around several groups of followers. One group was the familiares regis, John's immediate friends and knights who travelled around the country with him. They also played an important role in organising and leading military campaigns. Another section of royal followers were the curia regis; these curiales were the senior officials and agents of the king and were essential to his day-to-day rule. Being a member of these inner circles brought huge advantages, as it was easier to gain favours from the king, file lawsuits, marry a wealthy heiress or have one's debts remitted. By the time of Henry II, these posts were increasingly being filled by "new men" from outside the normal ranks of the barons. This intensified under John's rule, with many lesser nobles arriving from the continent to take up positions at court; many were mercenary leaders from Poitou. These men included soldiers who would become infamous in England for their uncivilised behaviour, including Falkes de Breauté, Geard d'Athies, Engelard de Cigongé and Philip Marc. Many barons perceived the king's household as what Ralph Turner has characterised as a "narrow clique enjoying royal favour at barons' expense" staffed by men of lesser status.


John's lack of religious conviction has been noted by contemporary chroniclers and later historians, with some suspecting that John was at best impious, or even atheistic, a very serious issue at the time. Contemporary chroniclers catalogued his various anti-religious habits at length, including his failure to take communion, his blasphemous remarks, and his witty but scandalous jokes about church doctrine, including jokes about the implausibility of the Resurrection. They commented on the paucity of John's charitable donations to the church. Historian Frank McLynn argues that John's early years at Fontevrault, combined with his relatively advanced education, may have turned him against the church. Other historians have been more cautious in interpreting this material, noting that chroniclers also reported John's personal interest in the life of St Wulfstan of Worcester and his friendships with several senior clerics, most especially with Hugh of Lincoln, who was later declared a saint. Financial records show a normal royal household engaged in the usual feasts and pious observances – albeit with many records showing John's offerings to the poor to atone for routinely breaking church rules and guidance. The historian Lewis Warren has argued that the chronicler accounts were subject to considerable bias and the King was "at least conventionally devout," citing his pilgrimages and interest in religious scripture and commentaries.


During the truce of 1206–1208, John focused on building up his financial and military resources in preparation for another attempt to recapture Normandy. John used some of this money to pay for new alliances on Philip's eastern frontiers, where the growth in Capetian power was beginning to concern France's neighbours. By 1212 John had successfully concluded alliances with his nephew Otto IV, a contender for the crown of Holy Roman Emperor in Germany, as well as with the counts Renaud of Boulogne and Ferdinand of Flanders. The invasion plans for 1212 were postponed because of fresh English baronial unrest about service in Poitou. Philip seized the initiative in 1213, sending his elder son, Louis, to invade Flanders with the intention of next launching an invasion of England. John was forced to postpone his own invasion plans to counter this threat. He launched his new fleet to attack the French at the harbour of Damme. The attack was a success, destroying Philip's vessels and any chances of an invasion of England that year. John hoped to exploit this advantage by invading himself late in 1213, but baronial discontent again delayed his invasion plans until early 1214, in what would prove to be his final Continental campaign.


John wanted John de Gray, the Bishop of Norwich and one of his own supporters, to be appointed Archbishop of Canterbury after the death of Walter, but the cathedral chapter for Canterbury Cathedral claimed the exclusive right to elect Walter's successor. They favoured Reginald, the chapter's sub-prior. To complicate matters, the bishops of the province of Canterbury also claimed the right to appoint the next archbishop. The chapter secretly elected Reginald and he travelled to Rome to be confirmed; the bishops challenged the appointment and the matter was taken before Innocent. John forced the Canterbury chapter to change their support to John de Gray, and a messenger was sent to Rome to inform the papacy of the new decision. Innocent disavowed both Reginald and John de Gray, and instead appointed his own candidate, Stephen Langton. John refused Innocent's request that he consent to Langton's appointment, but the pope consecrated Langton anyway in June 1207.


Tensions between John and the barons had been growing for several years, as demonstrated by the 1212 plot against the king. Many of the disaffected barons came from the north of England; that faction was often labelled by contemporaries and historians as "the Northerners". The northern barons rarely had any personal stake in the conflict in France, and many of them owed large sums of money to John; the revolt has been characterised as "a rebellion of the king's debtors". Many of John's military household joined the rebels, particularly amongst those that John had appointed to administrative roles across England; their local links and loyalties outweighed their personal loyalty to John. Tension also grew across North Wales, where opposition to the 1211 treaty between John and Llywelyn was turning into open conflict. For some the appointment of Peter des Roches as justiciar was an important factor, as he was considered an "abrasive foreigner" by many of the barons. The failure of John's French military campaign in 1214 was probably the final straw that precipitated the baronial uprising during John's final years as king; James Holt describes the path to civil war as "direct, short and unavoidable" following the defeat at Bouvines.


John met the rebel leaders at Runnymede, near Windsor Castle, on 15 June 1215. Langton's efforts at mediation created a charter capturing the proposed peace agreement; it was later renamed Magna Carta, or "Great Charter". The charter went beyond simply addressing specific baronial complaints, and formed a wider proposal for political reform, albeit one focusing on the rights of free men, not serfs and unfree labour. It promised the protection of church rights, protection from illegal imprisonment, access to swift justice, new taxation only with baronial consent and limitations on scutage and other feudal payments. A council of twenty-five barons would be created to monitor and ensure John's future adherence to the charter, whilst the rebel army would stand down and London would be surrendered to the king.


Prince Louis intended to land in the south of England in May 1216, and John assembled a naval force to intercept him. Unfortunately for John, his fleet was dispersed by bad storms and Louis landed unopposed in Kent. John hesitated and decided not to attack Louis immediately, either due to the risks of open battle or over concerns about the loyalty of his own men. Louis and the rebel barons advanced west and John retreated, spending the summer reorganising his defences across the rest of the kingdom. John saw several of his military household desert to the rebels, including his half-brother, William Longespée. By the end of the summer the rebels had regained the south-east of England and parts of the north.


John's first wife, Isabel, Countess of Gloucester, was released from imprisonment in 1214; she remarried twice, and died in 1217. John's second wife, Isabella of Angoulême, left England for Angoulême soon after the king's death; she became a powerful regional leader, but largely abandoned the children she had had by John. John had five legitimate children, all by Isabella. His eldest son, Henry III, ruled as king for the majority of the 13th century. Richard became a noted European leader and ultimately the King of the Romans in the Holy Roman Empire. Joan married Alexander II of Scotland to become his queen consort. Isabella married the Holy Roman Emperor Frederick II. His youngest daughter, Eleanor, married William Marshal's son, also called William, and later the famous English rebel Simon de Montfort. John had a number of illegitimate children by various mistresses, including nine sons – Richard, Oliver, John, Geoffrey, Henry, Osbert Gifford, Eudes, Bartholomew and probably Philip – and three daughters – Joan, Maud and probably Isabel. Of these, Joan became the most famous, marrying Prince Llywelyn the Great of Wales.


Most historians today, including John's recent biographers Ralph Turner and Lewis Warren, argue that John was an unsuccessful monarch, but note that his failings were exaggerated by 12th- and 13th-century chroniclers. Jim Bradbury notes the current consensus that John was a "hard-working administrator, an able man, an able general", albeit, as Turner suggests, with "distasteful, even dangerous personality traits", including pettiness, spitefulness and cruelty. John Gillingham, author of a major biography of Richard I, follows this line too, although he considers John a less effective general than do Turner or Warren, and describes him "one of the worst kings ever to rule England". Bradbury takes a moderate line, but suggests that in recent years modern historians have been overly lenient towards John's numerous faults. Popular historian Frank McLynn maintains a counter-revisionist perspective on John, arguing that the king's modern reputation amongst historians is "bizarre", and that as a monarch John "fails almost all those [tests] that can be legitimately set".


The Macintosh, however, was expensive, which hindered its ability to be competitive in a market already dominated by the Commodore 64 for consumers, as well as the IBM Personal Computer and its accompanying clone market for businesses. Macintosh systems still found success in education and desktop publishing and kept Apple as the second-largest PC manufacturer for the next decade. In the 1990s, improvements in the rival Wintel platform, notably with the introduction of Windows 3.0, then Windows 95, gradually took market share from the more expensive Macintosh systems. The performance advantage of 68000-based Macintosh systems was eroded by Intel's Pentium, and in 1994 Apple was relegated to third place as Compaq became the top PC manufacturer. Even after a transition to the superior PowerPC-based Power Macintosh (later renamed the PowerMac, in line with the PowerBook series) line in 1994, the falling prices of commodity PC components and the release of Windows 95 saw the Macintosh user base decline.


Smith's first Macintosh board was built to Raskin's design specifications: it had 64 kilobytes (kB) of RAM, used the Motorola 6809E microprocessor, and was capable of supporting a 256×256-pixel black-and-white bitmap display. Bud Tribble, a member of the Mac team, was interested in running the Apple Lisa's graphical programs on the Macintosh, and asked Smith whether he could incorporate the Lisa's Motorola 68000 microprocessor into the Mac while still keeping the production cost down. By December 1980, Smith had succeeded in designing a board that not only used the 68000, but increased its speed from 5 MHz to 8 MHz; this board also had the capacity to support a 384×256-pixel display. Smith's design used fewer RAM chips than the Lisa, which made production of the board significantly more cost-efficient. The final Mac design was self-contained and had the complete QuickDraw picture language and interpreter in 64 kB of ROM – far more than most other computers; it had 128 kB of RAM, in the form of sixteen 64 kilobit (kb) RAM chips soldered to the logicboard. Though there were no memory slots, its RAM was expandable to 512 kB by means of soldering sixteen IC sockets to accept 256 kb RAM chips in place of the factory-installed chips. The final product's screen was a 9-inch, 512x342 pixel monochrome display, exceeding the size of the planned screen.


Apple spent $2.5 million purchasing all 39 advertising pages in a special, post-election issue of Newsweek, and ran a "Test Drive a Macintosh" promotion, in which potential buyers with a credit card could take home a Macintosh for 24 hours and return it to a dealer afterwards. While 200,000 people participated, dealers disliked the promotion, the supply of computers was insufficient for demand, and many were returned in such a bad condition that they could no longer be sold. This marketing campaign caused CEO John Sculley to raise the price from US$1,995 to US$2,495 (about $5,200 when adjusted for inflation in 2010). The computer sold well, nonetheless, reportedly outselling the IBM PCjr which also began shipping early that year. By April 1984 the company sold 50,000 Macintoshes, and hoped for 70,000 by early May and almost 250,000 by the end of the year.


Apple released the Macintosh Plus on January 10, 1986, for a price of US$2,600. It offered one megabyte of RAM, easily expandable to four megabytes by the use of socketed RAM boards. It also featured a SCSI parallel interface, allowing up to seven peripherals—such as hard drives and scanners—to be attached to the machine. Its floppy drive was increased to an 800 kB capacity. The Mac Plus was an immediate success and remained in production, unchanged, until October 15, 1990; on sale for just over four years and ten months, it was the longest-lived Macintosh in Apple's history. In September 1986, Apple introduced the Macintosh Programmer's Workshop, or MPW, an application that allowed software developers to create software for Macintosh on Macintosh, rather than cross compiling from a Lisa. In August 1987, Apple unveiled HyperCard and MultiFinder, which added cooperative multitasking to the Macintosh. Apple began bundling both with every Macintosh.


With the new Motorola 68030 processor came the Macintosh IIx in 1988, which had benefited from internal improvements, including an on-board MMU. It was followed in 1989 by the Macintosh IIcx, a more compact version with fewer slots  and a version of the Mac SE powered by the 16 MHz 68030, the Macintosh SE/30. Later that year, the Macintosh IIci, running at 25 MHz, was the first Mac to be "32-bit clean." This allowed it to natively support more than 8 MB of RAM, unlike its predecessors, which had "32-bit dirty" ROMs (8 of the 32 bits available for addressing were used for OS-level flags). System 7 was the first Macintosh operating system to support 32-bit addressing. The following year, the Macintosh IIfx, starting at US$9,900, was unveiled. Apart from its fast 40 MHz 68030 processor, it had significant internal architectural improvements, including faster memory and two Apple II CPUs (6502s) dedicated to I/O processing.


As for Mac OS, System 7 was a 32-bit rewrite from Pascal to C++ that introduced virtual memory and improved the handling of color graphics, as well as memory addressing, networking, and co-operative multitasking. Also during this time, the Macintosh began to shed the "Snow White" design language, along with the expensive consulting fees they were paying to Frogdesign. Apple instead brought the design work in-house by establishing the Apple Industrial Design Group, becoming responsible for crafting a new look for all Apple products.


When Steve Jobs returned to Apple in 1997 following the company's purchase of NeXT, he ordered that the OS that had been previewed as version 7.7 be branded Mac OS 8 (in place of the never-to-appear Copland OS). Since Apple had licensed only System 7 to third parties, this move effectively ended the clone line. The decision caused significant financial losses for companies like Motorola, who produced the StarMax; Umax, who produced the SuperMac; and Power Computing, who offered several lines of Mac clones, including the PowerWave, PowerTower, and PowerTower Pro. These companies had invested substantial resources in creating their own Mac-compatible hardware. Apple bought out Power Computing's license, but allowed Umax to continue selling Mac clones until their license expired, as they had a sizeable presence in the lower-end segment that Apple did not. In September 1997 Apple extended Umax' license allowing them to sell clones with Mac OS 8, the only clone maker to do so, but with the restriction that they only sell low-end systems. Without the higher profit margins of high-end systems, however, Umax judged this would not be profitable and exited the Mac clone market in May 1998, having lost USD$36 million on the program.


Mac OS continued to evolve up to version 9.2.2, including retrofits such as the addition of a nanokernel and support for Multiprocessing Services 2.0 in Mac OS 8.6, though its dated architecture made replacement necessary. Initially developed in the Pascal programming language, it was substantially rewritten in C++ for System 7. From its beginnings on an 8 MHz machine with 128 KB of RAM, it had grown to support Apple's latest 1 GHz G4-equipped Macs. Since its architecture was laid down, features that were already common on Apple's competition, like preemptive multitasking and protected memory, had become feasible on the kind of hardware Apple manufactured. As such, Apple introduced Mac OS X, a fully overhauled Unix-based successor to Mac OS 9. OS X uses Darwin, XNU, and Mach as foundations, and is based on NeXTSTEP. It was released to the public in September 2000, as the Mac OS X Public Beta, featuring a revamped user interface called "Aqua". At US$29.99, it allowed adventurous Mac users to sample Apple's new operating system and provide feedback for the actual release. The initial version of Mac OS X, 10.0 "Cheetah", was released on March 24, 2001. Older Mac OS applications could still run under early Mac OS X versions, using an environment called "Classic". Subsequent releases of Mac OS X included 10.1 "Puma" (2001), 10.2 "Jaguar" (2002), 10.3 "Panther" (2003) and 10.4 "Tiger" (2005).


The current Mac product family uses Intel x86-64 processors. Apple introduced an emulator during the transition from PowerPC chips (called Rosetta), much as it did during the transition from Motorola 68000 architecture a decade earlier. The Macintosh is the only mainstream computer platform to have successfully transitioned to a new CPU architecture, and has done so twice. All current Mac models ship with at least 8 GB of RAM as standard other than the 1.4 GHz Mac Mini, MacBook Pro (without Retina Display), and MacBook Air. Current Mac computers use ATI Radeon or nVidia GeForce graphics cards as well as Intel graphics built into the main CPU. All current Macs (except for the MacBook Pro without Retina Display) do not ship with an optical media drive that includes a dual-function DVD/CD burner. Apple refers to this as a SuperDrive. Current Macs include two standard data transfer ports: USB and Thunderbolt (except for the MacBook (2015 version), which only has a USB-C port and headphone port). MacBook Pro, iMac, MacBook Air, and Mac Mini computers now also feature the "Thunderbolt" port, which Apple says can transfer data at speeds up to 10 gigabits per second. USB was introduced in the 1998 iMac G3 and is ubiquitous today, while FireWire is mainly reserved for high-performance devices such as hard drives or video cameras. Starting with the then-new iMac G5, released in October 2005, Apple started to include built-in iSight cameras on appropriate models, and a media center interface called Front Row that can be operated by an Apple Remote or keyboard for accessing media stored on the computer. Front Row has been discontinued as of 2011, however, and the Apple Remote is no longer bundled with new Macs.


Originally, the hardware architecture was so closely tied to the Mac OS operating system that it was impossible to boot an alternative operating system. The most common workaround, is to boot into Mac OS and then to hand over control to a Mac OS-based bootloader application. Used even by Apple for A/UX and MkLinux, this technique is no longer necessary since the introduction of Open Firmware-based PCI Macs, though it was formerly used for convenience on many Old World ROM systems due to bugs in the firmware implementation.[citation needed] Now, Mac hardware boots directly from Open Firmware in most PowerPC-based Macs or EFI in all Intel-based Macs.


In 1982, Regis McKenna was brought in to shape the marketing and launch of the Macintosh. Later the Regis McKenna team grew to include Jane Anderson, Katie Cadigan and Andy Cunningham, who eventually led the Apple account for the agency. Cunningham and Anderson were the primary authors of the Macintosh launch plan. The launch of the Macintosh pioneered many different tactics that are used today in launching technology products, including the "multiple exclusive," event marketing (credited to John Sculley, who brought the concept over from Pepsi), creating a mystique around a product and giving an inside look into a product's creation.


Compaq, who had previously held the third place spot among PC manufacturers during the 1980s and early-mid 1990s, initiated a successful price war in 1994 that vaulted them to the biggest by the year end, overtaking a struggling IBM and relegating Apple to third place. Apple's market share further struggled due to the release of the Windows 95 operating system, which unified Microsoft's formerly separate MS-DOS and Windows products. Windows 95 significantly enhanced the multimedia capability and performance of IBM PC compatible computers, and brought the capabilities of Windows to parity with the Mac OS GUI.


Statistics from late 2003 indicate that Apple had 2.06 percent of the desktop share in the United States that had increased to 2.88 percent by Q4 2004. As of October 2006, research firms IDC and Gartner reported that Apple's market share in the U.S. had increased to about 6 percent. Figures from December 2006, showing a market share around 6 percent (IDC) and 6.1 percent (Gartner) are based on a more than 30 percent increase in unit sale from 2005 to 2006. The installed base of Mac computers is hard to determine, with numbers ranging from 5% (estimated in 2009) to 16% (estimated in 2005).


The Macintosh SE was released at the same time as the Macintosh II for $2900 (or $3900 with hard drive), as the first compact Mac with a 20 MB internal hard drive and an expansion slot. The SE's expansion slot was located inside the case along with the CRT, potentially exposing an upgrader to high voltage. For this reason, Apple recommended users bring their SE to an authorized Apple dealer to have upgrades performed. The SE also updated Jerry Manock and Terry Oyama's original design and shared the Macintosh II's Snow White design language, as well as the new Apple Desktop Bus (ADB) mouse and keyboard that had first appeared on the Apple IIGS some months earlier.


In recent years, Apple has seen a significant boost in sales of Macs. This has been attributed, in part, to the success of the iPod and the iPhone, a halo effect whereby satisfied iPod or iPhone owners purchase more Apple products, and Apple has since capitalized on that with the iCloud cloud service that allows users to seamlessly sync data between these devices and Macs. Nonetheless, like other personal computer manufacturers, the Macintosh lines have been hurt by consumer trend towards smartphones and tablet computers (particularly Apple's own iPhone and iPad, respectively) as the computing devices of choice among consumers.


In response, Apple introduced a range of relatively inexpensive Macs in October 1990. The Macintosh Classic, essentially a less expensive version of the Macintosh SE, was the least expensive Mac offered until early 2001. The 68020-powered Macintosh LC, in its distinctive "pizza box" case, offered color graphics and was accompanied by a new, low-cost 512×384 pixel monitor. The Macintosh IIsi was essentially a 20 MHz IIci with only one expansion slot. All three machines sold well, although Apple's profit margin on them was considerably lower than that on earlier models.


Starting in 2006, Apple's industrial design shifted to favor aluminum, which was used in the construction of the first MacBook Pro. Glass was added in 2008 with the introduction of the unibody MacBook Pro. These materials are billed as environmentally friendly. The iMac, MacBook Pro, MacBook Air, and Mac Mini lines currently all use aluminum enclosures, and are now made of a single unibody. Chief designer Jonathan Ive continues to guide products towards a minimalist and simple feel, including eliminating of replaceable batteries in notebooks. Multi-touch gestures from the iPhone's interface have been applied to the Mac line in the form of touch pads on notebooks and the Magic Mouse and Magic Trackpad for desktops.


The Macintosh project was begun in 1979 by Jef Raskin, an Apple employee who envisioned an easy-to-use, low-cost computer for the average consumer. He wanted to name the computer after his favorite type of apple, the McIntosh, but the spelling was changed to "Macintosh" for legal reasons as the original was the same spelling as that used by McIntosh Laboratory, Inc., the audio equipment manufacturer. Steve Jobs requested that McIntosh Laboratory give Apple a release for the name with its changed spelling so that Apple could use it, but the request was denied, forcing Apple to eventually buy the rights to use the name. (A 1984 Byte Magazine article suggested Apple changed the spelling only after "early users" misspelled "McIntosh". However, Jef Raskin had adopted the Macintosh spelling by 1981, when the Macintosh computer was still a single prototype machine in the lab. This explanation further clashes with the first explanation given above that the change was made for "legal reasons.")


After the Lisa's announcement, John Dvorak discussed rumors of a mysterious "MacIntosh" project at Apple in February 1983. The company announced the Macintosh 128K—manufactured at an Apple factory in Fremont, California—in October 1983, followed by an 18-page brochure included with various magazines in December. The Macintosh was introduced by a US$1.5 million Ridley Scott television commercial, "1984". It most notably aired during the third quarter of Super Bowl XVIII on January 22, 1984, and is now considered a "watershed event" and a "masterpiece." Regis McKenna called the ad "more successful than the Mac itself." "1984" used an unnamed heroine to represent the coming of the Macintosh (indicated by a Picasso-style picture of the computer on her white tank top) as a means of saving humanity from the "conformity" of IBM's attempts to dominate the computer industry. The ad alludes to George Orwell's novel, Nineteen Eighty-Four, which described a dystopian future ruled by a televised "Big Brother."


The Macintosh (/ˈmækᵻntɒʃ/ MAK-in-tosh; branded as Mac since 1997) is a series of personal computers (PCs) designed, developed, and marketed by Apple Inc. Steve Jobs introduced the original Macintosh computer on January 24, 1984. This was the first mass-market personal computer featuring an integral graphical user interface and mouse. This first model was later renamed to "Macintosh 128k" for uniqueness amongst a populous family of subsequently updated models which are also based on Apple's same proprietary architecture. Since 1998, Apple has largely phased out the Macintosh name in favor of "Mac", though the product family has been nicknamed "Mac" or "the Mac" since the development of the first model.


In 1985, the combination of the Mac, Apple's LaserWriter printer, and Mac-specific software like Boston Software's MacPublisher and Aldus PageMaker enabled users to design, preview, and print page layouts complete with text and graphics—an activity to become known as desktop publishing. Initially, desktop publishing was unique to the Macintosh, but eventually became available for other platforms. Later, applications such as Macromedia FreeHand, QuarkXPress, and Adobe's Photoshop and Illustrator strengthened the Mac's position as a graphics computer and helped to expand the emerging desktop publishing market.


Raskin was authorized to start hiring for the project in September 1979, and he immediately asked his long-time colleague, Brian Howard, to join him. His initial team would eventually consist of himself, Howard, Joanna Hoffman, Burrell Smith, and Bud Tribble. The rest of the original Mac team would include Bill Atkinson, Bob Belleville, Steve Capps, George Crow, Donn Denman, Chris Espinosa, Andy Hertzfeld, Bruce Horn, Susan Kare, Larry Kenyon, and Caroline Rose with Steve Jobs leading the project.


From 2001 to 2008, Mac sales increased continuously on an annual basis. Apple reported worldwide sales of 3.36 million Macs during the 2009 holiday season. As of Mid-2011, the Macintosh continues to enjoy rapid market share increase in the US, growing from 7.3% of all computer shipments in 2010 to 9.3% in 2011. According to IDC's quarterly PC tracker, globally, in 3rd quarter of 2014, Apple's PC market share increased 5.7 percent year over year, with record sales of 5.5 million units. Apple now sits in the number five spot, with a global market share of about 6% during 2014, behind Lenovo, HP, Dell and Acer.


In 1987, Apple spun off its software business as Claris. It was given the code and rights to several applications, most notably MacWrite, MacPaint, and MacProject. In the late 1980s, Claris released a number of revamped software titles; the result was the "Pro" series, including MacDraw Pro, MacWrite Pro, and FileMaker Pro. To provide a complete office suite, Claris purchased the rights to the Informix Wingz spreadsheet program on the Mac, renaming it Claris Resolve, and added the new presentation software Claris Impact. By the early 1990s, Claris applications were shipping with the majority of consumer-level Macintoshes and were extremely popular. In 1991, Claris released ClarisWorks, which soon became their second best-selling application. When Claris was reincorporated back into Apple in 1998, ClarisWorks was renamed AppleWorks beginning with version 5.0.


Two days after "1984" aired, the Macintosh went on sale, and came bundled with two applications designed to show off its interface: MacWrite and MacPaint. It was first demonstrated by Steve Jobs in the first of his famous Mac keynote speeches, and though the Mac garnered an immediate, enthusiastic following, some labeled it a mere "toy." Because the operating system was designed largely around the GUI, existing text-mode and command-driven applications had to be redesigned and the programming code rewritten. This was a time-consuming task that many software developers chose not to undertake, and could be regarded as a reason for an initial lack of software for the new system. In April 1984, Microsoft's MultiPlan migrated over from MS-DOS, with Microsoft Word following in January 1985. In 1985, Lotus Software introduced Lotus Jazz for the Macintosh platform after the success of Lotus 1-2-3 for the IBM PC, although it was largely a flop. Apple introduced the Macintosh Office suite the same year with the "Lemmings" ad. Infamous for insulting its own potential customers, the ad was not successful.


Apple has generally dominated the premium PC market, having a 91 percent market share for PCs priced at more than $1,000 in 2009, according to NPD. The Macintosh took 45 percent of operating profits in the PC industry during Q4 2012, compared to 13 percent for Dell, seven percent for Hewlett Packard, six percent for Lenovo and Asus, and one percent for Acer. While sales of the Macintosh have largely held steady, in comparison to Apple's sales of the iPhone and iPad which increased significantly during the 2010s, Macintosh computers still enjoy high margins on a per unit basis, with the majority being their MacBooks that are focused on the ultraportable niche that is the most profitable and only growing segment of PCs. It also helped that the Macintosh lineup is simple, updated on a yearly schedule, and consistent across both Apple retail stores, and authorized resellers where they have a special "store within a store" section to distinguish them from Windows PCs. In contrast, Windows PC manufacturers generally have a wide range of offerings, selling only a portion through retail with a full selection on the web, and often with limited-time or region-specific models. The Macintosh ranked third on the "list of intended brands for desktop purchases" for the 2011 holiday season, then moved up to second in 2012 by displacing Hewlett Packard, and in 2013 took the top spot ahead of Dell.


The Macintosh's minimal memory became apparent, even compared with other personal computers in 1984, and could not be expanded easily. It also lacked a hard disk drive or the means to easily attach one. Many small companies sprang up to address the memory issue. Suggestions revolved around either upgrading the memory to 512 KB or removing the computer's 16 memory chips and replacing them with larger-capacity chips, a tedious and difficult operation. In October 1984, Apple introduced the Macintosh 512K, with quadruple the memory of the original, at a price of US$3,195. It also offered an upgrade for 128k Macs that involved replacing the logic board.


In 1988, Apple sued Microsoft and Hewlett-Packard on the grounds that they infringed Apple's copyrighted GUI, citing (among other things) the use of rectangular, overlapping, and resizable windows. After four years, the case was decided against Apple, as were later appeals. Apple's actions were criticized by some in the software community, including the Free Software Foundation (FSF), who felt Apple was trying to monopolize on GUIs in general, and boycotted GNU software for the Macintosh platform for seven years.


Furthermore, Apple had created too many similar models that confused potential buyers. At one point, its product lineup was subdivided into Classic, LC, II, Quadra, Performa, and Centris models, with essentially the same computer being sold under a number of different names. These models competed against Macintosh clones, hardware manufactured by third parties that ran Apple's System 7. This succeeded in increasing the Macintosh's market share somewhat, and provided cheaper hardware for consumers, but hurt Apple financially as existing Apple customers began to buy cheaper clones which cannibalized the sales of Apple's higher-margin Macintosh systems, yet Apple still shouldered the burden of developing the Mac OS platform.


In early 2001, Apple began shipping computers with CD-RW drives and emphasized the Mac's ability to play DVDs by including DVD-ROM and DVD-RAM drives as standard. Steve Jobs admitted that Apple had been "late to the party" on writable CD technology, but felt that Macs could become a "digital hub" that linked and enabled an "emerging digital lifestyle". Apple would later introduce an update to its iTunes music player software that enabled it to burn CDs, along with a controversial "Rip, Mix, Burn" advertising campaign that some felt encouraged media piracy. This accompanied the release of the iPod, Apple's first successful handheld device. Apple continued to launch products, such as the unsuccessful Power Mac G4 Cube, the education-oriented eMac, and the titanium (and later aluminium) PowerBook G4 laptop for professionals.


It was not long until Apple released their first portable computer, the Macintosh Portable in 1989. Although due to considerable design issues, it was soon replaced in 1991 with the first of the PowerBook line: the PowerBook 100, a miniaturized portable; the 16 MHz 68030 PowerBook 140; and the 25 MHz 68030 PowerBook 170. They were the first portable computers with the keyboard behind a palm rest and a built-in pointing device (a trackball) in front of the keyboard. The 1993 PowerBook 165c was Apple's first portable computer to feature a color screen, displaying 256 colors with 640 x 400-pixel resolution. The second generation of PowerBooks, the 68040-equipped 500 series, introduced trackpads, integrated stereo speakers, and built-in Ethernet to the laptop form factor in 1994.


In 2001, Apple introduced Mac OS X, based on Darwin and NEXTSTEP; its new features included the Dock and the Aqua user interface. During the transition, Apple included a virtual machine subsystem known as Classic, allowing users to run Mac OS 9 applications under Mac OS X 10.4 and earlier on PowerPC machines. Apple introduced Mac OS X 10.8 in February, and it was made available in the summer of 2012. Mountain Lion includes many new features, such as Mission Control, the Mac App Store (available to Mac OS X v10.6.6 "Snow Leopard." users by software update), Launchpad, an application viewer and launcher akin to the iOS Home Screen, and Resume, a feature similar to the hibernate function found in Microsoft Windows. The most recent version is OS X El Capitan . In addition to Mavericks, all new Macs are bundled with assorted Apple-produced applications, including iLife, the Safari web browser and the iTunes media player. Apple introduced Mavericks at WWDC 2013 in June, and released it on October 15 of that year. It is free of charge to everyone running Snow Leopard or later and is compatible with most Macs from 2007 and later. Mavericks brought a lot of the iOS apps, functions, and feel to the Mac as well as better multi display support, iBooks, Maps, app nap, and other upgrades to improve performance and battery life.


In 2000, Apple released the Power Mac G4 Cube, their first desktop since the discontinued Power Macintosh G3, to slot between the iMac G3 and the Power Mac G4. Even with its innovative design, it was initially priced US$200 higher than the comparably-equipped and more-expandable base Power Mac G4, while also not including a monitor, making it too expensive and resulting in slow sales. Apple sold just 29,000 Cubes in Q4 of 2000 which was one third of expectations, compared to 308,000 Macs during that same quarter, and Cube sales dropped to 12,000 units in Q1 of 2001. A price drop and hardware upgrades could not offset the earlier perception of the Cube's reduced value compared to the iMac and Power Mac G4 lineup, and it was discontinued in July 2001.


Historically, Mac OS X enjoyed a near-absence of the types of malware and spyware that affect Microsoft Windows users. Mac OS X has a smaller usage share compared to Microsoft Windows (roughly 5% and 92%, respectively), but it also has traditionally more secure UNIX roots. Worms, as well as potential vulnerabilities, were noted in February 2006, which led some industry analysts and anti-virus companies to issue warnings that Apple's Mac OS X is not immune to malware. Increasing market share coincided with additional reports of a variety of attacks. Apple releases security updates for its software. In early 2011, Mac OS X experienced a large increase in malware attacks, and malware such as Mac Defender, MacProtector, and MacGuard were seen as an increasing problem for Mac users. At first, the malware installer required the user to enter the administrative password, but later versions were able to install without user input. Initially, Apple support staff were instructed not to assist in the removal of the malware or admit the existence of the malware issue, but as the malware spread, a support document was issued. Apple announced an OS X update to fix the problem. An estimated 100,000 users were affected.


By March 2011, the market share of OS X in North America had increased to slightly over 14%. Whether the size of the Mac's market share and installed base is relevant, and to whom, is a hotly debated issue. Industry pundits have often called attention to the Mac's relatively small market share to predict Apple's impending doom, particularly in the early and mid-1990s when the company's future seemed bleakest. Others argue that market share is the wrong way to judge the Mac's success. Apple has positioned the Mac as a higher-end personal computer, and so it may be misleading to compare it to a budget PC. Because the overall market for personal computers has grown rapidly, the Mac's increasing sales numbers are effectively swamped by the industry's expanding sales volume as a whole. Apple's small market share, then, gives the impression that fewer people are using Macs than did ten years ago, when exactly the opposite is true. Soaring sales of the iPhone and iPad mean that the portion of Apple's profits represented by the Macintosh has declined in 2010, dropping to 24% from 46% two years earlier. Others try to de-emphasize market share, citing that it is rarely brought up in other industries. Regardless of the Mac's market share, Apple has remained profitable since Steve Jobs' return and the company's subsequent reorganization. Notably, a report published in the first quarter of 2008 found that Apple had a 14% market share in the personal computer market in the US, including 66% of all computers over $1,000. Market research indicates that Apple draws its customer base from a higher-income demographic than the mainstream personal computer market.


Notwithstanding these technical and commercial successes on the Macintosh platform, their systems remained fairly expensive, making them less competitive in light of the falling costs of components that made IBM PC compatibles cheaper and accelerated their adoption. In 1989, Jean-Louis Gassée had steadfastly refused to lower the profit margins on Mac computers, then there was a component shortage that rocked the exponentially-expanding PC industry that year, forcing Apple USA head Allan Loren to cut prices which dropped Apple's margins. Microsoft Windows 3.0 was released in May 1990, the first iteration of Windows which had a feature set and performance comparable to the significantly costlier Macintosh. Furthermore, Apple had created too many similar models that confused potential buyers; at one point the product lineup was subdivided into Classic, LC, II, Quadra, Performa, and Centris models, with essentially the same computer being sold under a number of different names.


Starting in 2002, Apple moved to eliminate CRT displays from its product line as part of aesthetic design and space-saving measures with the iMac G4. However, the new iMac with its flexible LCD flat-panel monitor was considerably more expensive on its debut than the preceding iMac G3, largely due to the higher cost of the LCD technology at the time. In order to keep the Macintosh affordable for the education market and due to obsolescence of the iMac G3, Apple created the eMac in April 2002 as the intended successor; however the eMac's CRT made it relatively bulky and somewhat outdated, while its all-in-one construction meant it could not be expanded to meet consumer demand for larger monitors. The iMac G4's relatively high prices were approaching that of laptops which were portable and had higher resolution LCD screens. Meanwhile, Windows PC manufacturers could offer desktop configurations with LCD flat panel monitors at prices comparable to the eMac and at much lower cost than the iMac G4. The flop of the Power Mac G4 Cube, along with the more expensive iMac G4 and heavy eMac, meant that Macintosh desktop sales never reached the market share attained by the previous iMac G3. For the next half-decade while Macintosh sales held steady, it would instead be the iPod portable music player and iTunes music download service that would drive Apple's sales growth.


The sales breakdown of the Macintosh have seen sales of desktop Macs stayed mostly constant while being surpassed by that of Mac notebooks whose sales rate has grown considerably; seven out of ten Macs sold were laptops in 2009, a ratio projected to rise to three out of four by 2010. The change in sales of form factors is due to the desktop iMac moving from affordable (iMac G3) to upscale (iMac G4) and subsequent releases are considered premium all-in-ones. By contrast the MSRP of the MacBook laptop lines have dropped through successive generations such that the MacBook Air and MacBook Pro constitute the lowest price of entry to a Mac, with the exception of the even more inexpensive Mac Mini (the only sub-$1000 offering from Apple, albeit without a monitor and keyboard), not surprisingly the MacBooks are the top-selling form factors of the Macintosh platform today. The use of Intel microprocessors has helped Macs more directly compete with their Windows counterparts on price and performance, and by the 2010s Apple was receiving Intel's latest CPUs first before other PC manufacturers.


In 1998, after the return of Steve Jobs, Apple consolidated its multiple consumer-level desktop models into the all-in-one iMac G3, which became a commercial success and revitalized the brand. Since their transition to Intel processors in 2006, the complete lineup is entirely based on said processors and associated systems. Its current lineup comprises three desktops (the all-in-one iMac, entry-level Mac mini, and the Mac Pro tower graphics workstation), and four laptops (the MacBook, MacBook Air, MacBook Pro, and MacBook Pro with Retina display). Its Xserve server was discontinued in 2011 in favor of the Mac Mini and Mac Pro.


Burrel's innovative design, which combined the low production cost of an Apple II with the computing power of Lisa's CPU, the Motorola 68K, received the attention of Steve Jobs, co-founder of Apple. Realizing that the Macintosh was more marketable than the Lisa, he began to focus his attention on the project. Raskin left the team in 1981 over a personality conflict with Jobs. Team member Andy Hertzfeld said that the final Macintosh design is closer to Jobs' ideas than Raskin's. After hearing of the pioneering GUI technology being developed at Xerox PARC, Jobs had negotiated a visit to see the Xerox Alto computer and its Smalltalk development tools in exchange for Apple stock options. The Lisa and Macintosh user interfaces were influenced by technology seen at Xerox PARC and were combined with the Macintosh group's own ideas. Jobs also commissioned industrial designer Hartmut Esslinger to work on the Macintosh line, resulting in the "Snow White" design language; although it came too late for the earliest Macs, it was implemented in most other mid- to late-1980s Apple computers. However, Jobs' leadership at the Macintosh project did not last; after an internal power struggle with new CEO John Sculley, Jobs resigned from Apple in 1985. He went on to found NeXT, another computer company targeting the education market, and did not return until 1997, when Apple acquired NeXT.


Jobs stated during the Macintosh's introduction "we expect Macintosh to become the third industry standard", after the Apple II and IBM PC. Although outselling every other computer, it did not meet expectations during the first year, especially among business customers. Only about ten applications including MacWrite and MacPaint were widely available, although many non-Apple software developers participated in the introduction and Apple promised that 79 companies including Lotus, Digital Research, and Ashton-Tate were creating products for the new computer. After one year, it had less than one quarter of the software selection available compared to the IBM PC—including only one word processor, two databases, and one spreadsheet—although Apple had sold 280,000 Macintoshes compared to IBM's first year sales of fewer than 100,000 PCs.


Updated Motorola CPUs made a faster machine possible, and in 1987 Apple took advantage of the new Motorola technology and introduced the Macintosh II at $5500, powered by a 16 MHz Motorola 68020 processor. The primary improvement in the Macintosh II was Color QuickDraw in ROM, a color version of the graphics language which was the heart of the machine. Among the many innovations in Color QuickDraw were the ability to handle any display size, any color depth, and multiple monitors. The Macintosh II marked the start of a new direction for the Macintosh, as now for the first time it had an open architecture with several NuBus expansion slots, support for color graphics and external monitors, and a modular design similar to that of the IBM PC. It had an internal hard drive and a power supply with a fan, which was initially fairly loud. One third-party developer sold a device to regulate fan speed based on a heat sensor, but it voided the warranty. Later Macintosh computers had quieter power supplies and hard drives.


Microsoft Windows 3.0 was released in May 1990, and according to a common saying at the time "Windows was not as good as Macintosh, but it was good enough for the average user". Though still a graphical wrapper that relied upon MS-DOS, 3.0 was the first iteration of Windows which had a feature set and performance comparable to the much more expensive Macintosh platform. It also did not help matters that during the previous year Jean-Louis Gassée had steadfastly refused to lower the profit margins on Mac computers. Finally, there was a component shortage that rocked the exponentially-expanding PC industry in 1989, forcing Apple USA head Allan Loren to cut prices which dropped Apple's margins.


Intel had tried unsuccessfully to push Apple to migrate the Macintosh platform to Intel chips. Apple concluded that Intel's CISC (Complex Instruction Set Computer) architecture ultimately would not be able to compete against RISC (Reduced Instruction Set Computer) processors. While the Motorola 68040 offered the same features as the Intel 80486 and could on a clock-for-clock basis significantly outperform the Intel chip, the 486 had the ability to be clocked significantly faster without suffering from overheating problems, especially the clock-doubled i486DX2 which ran the CPU logic at twice the external bus speed, giving such equipped IBM compatible systems a significant performance lead over their Macintosh equivalents. Apple's product design and engineering didn't help matters as they restricted the use of the '040 to their expensive Quadras for a time while the 486 was readily available to OEMs as well as enthusiasts who put together their own machines. In late 1991, as the higher-end Macintosh desktop lineup transitioned to the '040, Apple was unable to offer the '040 in their top-of-the-line PowerBooks until early 1994 with the PowerBook 500 series, several years after the first 486-powered IBM compatible laptops hit the market which cost Apple considerable sales. In 1993 Intel rolled out the Pentium processors as the successor to the 486, while the Motorola 68050 was never released, leaving the Macintosh platform a generation behind IBM compatibles in the latest CPU technology. In 1994, Apple abandoned Motorola CPUs for the RISC PowerPC architecture developed by the AIM alliance of Apple Computer, IBM, and Motorola. The Power Macintosh line, the first to use the new chips, proved to be highly successful, with over a million PowerPC units sold in nine months. However, in the long run, spurning Intel for the PowerPC was a mistake as the commoditization of Intel-architecture chips meant Apple couldn't compete on price against "the Dells of the world".


In 1998, Apple introduced its new iMac which, like the original 128K Mac, was an all-in-one computer. Its translucent plastic case, originally Bondi blue and later various additional colors, is considered an industrial design landmark of the late 1990s. The iMac did away with most of Apple's standard (and usually proprietary) connections, such as SCSI and ADB, in favor of two USB ports. It replaced a floppy disk drive with a CD-ROM drive for installing software, but was incapable of writing to CDs or other media without external third-party hardware. The iMac proved to be phenomenally successful, with 800,000 units sold in 139 days. It made the company an annual profit of US$309 million, Apple's first profitable year since Michael Spindler took over as CEO in 1995. This aesthetic was applied to the Power Macintosh and later the iBook, Apple's first consumer-level laptop computer, filling the missing quadrant of Apple's "four-square product matrix" (desktop and portable products for both consumers and professionals). More than 140,000 pre-orders were placed before it started shipping in September, and by October proved to be a large success.


Apple discontinued the use of PowerPC microprocessors in 2006. At WWDC 2005, Steve Jobs announced this transition, revealing that Mac OS X was always developed to run on both the Intel and PowerPC architectures. All new Macs now use x86 processors made by Intel, and some were renamed as a result. Intel-based Macs running OS X 10.6 and below (support has been discontinued since 10.7) can run pre-existing software developed for PowerPC using an emulator called Rosetta, although at noticeably slower speeds than native programs. However, the Classic environment is unavailable on the Intel architecture. Intel chips introduced the potential to run the Microsoft Windows operating system natively on Apple hardware, without emulation software such as Virtual PC. In March 2006, a group of hackers announced that they were able to run Windows XP on an Intel-based Mac. The group released their software as open source and has posted it for download on their website. On April 5, 2006, Apple announced the availability of the public beta of Boot Camp, software that allows owners of Intel-based Macs to install Windows XP on their machines; later versions added support for Windows Vista and Windows 7. Classic was discontinued in Mac OS X 10.5, and Boot Camp became a standard feature on Intel-based Macs.


Apple was initially reluctant to embrace mice with multiple buttons and scroll wheels. Macs did not natively support pointing devices that featured multiple buttons, even from third parties, until Mac OS X arrived in 2001. Apple continued to offer only single button mice, in both wired and Bluetooth wireless versions, until August 2005, when it introduced the Mighty Mouse. While it looked like a traditional one-button mouse, it actually had four buttons and a scroll ball, capable of independent x- and y-axis movement. A Bluetooth version followed in July 2006. In October 2009, Apple introduced the Magic Mouse, which uses multi-touch gesture recognition (similar to that of the iPhone) instead of a physical scroll wheel or ball. It is available only in a wireless configuration, but the wired Mighty Mouse (re-branded as "Apple Mouse") is still available as an alternative. Since 2010, Apple has also offered the Magic Trackpad as a means to control Macintosh desktop computers in a way similar to laptops.


Following the release of Intel-based Macs, third-party platform virtualization software such as Parallels Desktop, VMware Fusion, and VirtualBox began to emerge. These programs allow users to run Microsoft Windows or previously Windows-only software on Macs at near native speed. Apple also released Boot Camp and Mac-specific Windows drivers that help users to install Windows XP or Vista and natively dual boot between Mac OS X and Windows. Though not condoned by Apple, it is possible to run the Linux operating system using Boot camp or other virtualization workarounds. Unlike most PCs, however, Macs are unable to run many legacy PC operating systems. In particular, Intel-based macs lack the A20 gate.


Although the PC market declined, Apple still managed to ship 2.8 million MacBooks in Q2 2012 (the majority of which are the MacBook Air) compared to 500,000 total Ultrabooks, although there were dozens of Ultrabooks from various manufacturers on the market while Apple only offered 11-inch and 13-inch models of the MacBook Air. The Air has been the best-selling ultra-portable in certain countries over Windows Ultrabooks, particularly the United States. While several Ultrabooks were able to claim individual distinctions such as being the lightest or thinnest, the Air was regarded by reviewers as the best all-around subnotebook/ultraportable in regard to "OS X experience, full keyboard, superior trackpad, Thunderbolt connector and the higher-quality, all-aluminum unibody construction". The Air was among the first to receive Intel's latest CPUs before other PC manufacturers, and OS X has gained market share on Windows in recent years. Through July 1, 2013, the MacBook Air took in 56 percent of all Ultrabook sales in the United States, although being one of the higher-priced competitors, though several Ultrabooks with better features were often more expensive than the MacBook Air. The competitive pricing of MacBooks was particularly effective when rivals charged more for seemingly equivalent Ultrabooks, as this contradicted the established "elitist aura" perception that Apple products cost more but were higher quality, which made these most expensive Ultrabooks seem exorbitant no matter how valid their higher prices were.


Anti-aircraft warfare or counter-air defence is defined by NATO as "all measures designed to nullify or reduce the effectiveness of hostile air action." They include ground-and air-based weapon systems, associated sensor systems, command and control arrangements and passive measures (e.g. barrage balloons). It may be used to protect naval, ground, and air forces in any location. However, for most countries the main effort has tended to be 'homeland defence'. NATO refers to airborne air defence as counter-air and naval air defence as anti-aircraft warfare. Missile defence is an extension of air defence as are initiatives to adapt air defence to the task of intercepting any projectile in flight.


Non-English terms for air defence include the German Flak (Fliegerabwehrkanone, "aircraft defence cannon", also cited as Flugabwehrkanone), whence English flak, and the Russian term Protivovozdushnaya oborona (Cyrillic: Противовозду́шная оборо́на), a literal translation of "anti-air defence", abbreviated as PVO. In Russian the AA systems are called zenitnye (i.e. "pointing to zenith") systems (guns, missiles etc.). In French, air defence is called DCA (Défense contre les aéronefs, "aéronef" being the generic term for all kind of airborne device (airplane, airship, balloon, missile, rocket, etc.)).


Initially sensors were optical and acoustic devices developed during the First World War and continued into the 1930s, but were quickly superseded by radar, which in turn was supplemented by optronics in the 1980s. Command and control remained primitive until the late 1930s, when Britain created an integrated system for ADGB that linked the ground-based air defence of the army's AA Command, although field-deployed air defence relied on less sophisticated arrangements. NATO later called these arrangements an "air defence ground environment", defined as "the network of ground radar sites and command and control centres within a specific theatre of operations which are used for the tactical control of air defence operations".


The most extreme case was the Soviet Union, and this model may still be followed in some countries: it was a separate service, on a par with the navy or ground force. In the Soviet Union this was called Voyska PVO, and had both fighter aircraft and ground-based systems. This was divided into two arms, PVO Strany, the Strategic Air defence Service responsible for Air Defence of the Homeland, created in 1941 and becoming an independent service in 1954, and PVO SV, Air Defence of the Ground Forces. Subsequently these became part of the air force and ground forces respectively


On 30 September 1915, troops of the Serbian Army observed three enemy aircraft approaching Kragujevac. Soldiers shot at them with shotguns and machine-guns but failed to prevent them from dropping 45 bombs over the city, hitting military installations, the railway station and many other, mostly civilian, targets in the city. During the bombing raid, private Radoje Ljutovac fired his cannon at the enemy aircraft and successfully shot one down. It crashed in the city and both pilots died from their injuries. The cannon Ljutovac used was not designed as an anti-aircraft gun, it was a slightly modified Turkish cannon captured during the First Balkan War in 1912. This was the first occasion in military history that a military aircraft was shot down with ground-to-air fire.


AA gunnery was a difficult business. The problem was of successfully aiming a shell to burst close to its target's future position, with various factors affecting the shells' predicted trajectory. This was called deflection gun-laying, 'off-set' angles for range and elevation were set on the gunsight and updated as their target moved. In this method when the sights were on the target, the barrel was pointed at the target's future position. Range and height of the target determined fuse length. The difficulties increased as aircraft performance improved.


World War I demonstrated that aircraft could be an important part of the battlefield, but in some nations it was the prospect of strategic air attack that was the main issue, presenting both a threat and an opportunity. The experience of four years of air attacks on London by Zeppelins and Gotha G.V bombers had particularly influenced the British and was one of if not the main driver for forming an independent air force. As the capabilities of aircraft and their engines improved it was clear that their role in future war would be even more critical as their range and weapon load grew. However, in the years immediately after World War I the prospect of another major war seemed remote, particularly in Europe where the most militarily capable nations were, and little financing was available.


From the early 1930s eight countries developed radar, these developments were sufficiently advanced by the late 1930s for development work on sound locating acoustic devices to be generally halted, although equipment was retained. Furthermore, in Britain the volunteer Observer Corps formed in 1925 provided a network of observation posts to report hostile aircraft flying over Britain. Initially radar was used for airspace surveillance to detect approaching hostile aircraft. However, the German Würzburg radar was capable of providing data suitable for controlling AA guns and the British AA No 1 Mk 1 GL radar was designed to be used on AA gun positions.


Until this time the British, at RAF insistence, continued their World War I use of machine guns, and introduced twin MG mountings for AAAD. The army was forbidden from considering anything larger than .50-inch. However, in 1935 their trials showed that the minimum effective round was an impact fused 2 lb HE shell. The following year they decided to adopt the Bofors 40 mm and a twin barrel Vickers 2-pdr (40 mm) on a modified naval mount. The air-cooled Bofors was vastly superior for land use, being much lighter than the water-cooled pom-pom, and UK production of the Bofors 40 mm was licensed. The Predictor AA No 3, as the Kerrison Predictor was officially known, was introduced with it.


During the 1930s solid fuel rockets were under development in the Soviet Union and Britain. In Britain the interest was for anti-aircraft fire, it quickly became clear that guidance would be required for precision. However, rockets, or 'unrotated projectiles' as they were called could the used for anti-aircraft barrages. A 2-inch rocket using HE or wire obstacle warheads was introduced first to deal with low-level or dive bombing attacks on smaller targets such as airfields. The 3-inch was in development at the end of the inter-war period.


The British had already arranged licence building of the Bofors 40 mm, and introduced these into service. These had the power to knock down aircraft of any size, yet were light enough to be mobile and easily swung. The gun became so important to the British war effort that they even produced a movie, The Gun, that encouraged workers on the assembly line to work harder. The Imperial measurement production drawings the British had developed were supplied to the Americans who produced their own (unlicensed) copy of the 40 mm at the start of the war, moving to licensed production in mid-1941.


The interceptor aircraft (or simply interceptor) is a type of fighter aircraft designed specifically to intercept and destroy enemy aircraft, particularly bombers, usually relying on high speed and altitude capabilities. A number of jet interceptors such as the F-102 Delta Dagger, the F-106 Delta Dart, and the MiG-25 were built in the period starting after the end of World War II and ending in the late 1960s, when they became less important due to the shifting of the strategic bombing role to ICBMs. Invariably the type is differentiated from other fighter aircraft designs by higher speeds and shorter operating ranges, as well as much reduced ordnance payloads.


Another potential weapon system for anti-aircraft use is the laser. Although air planners have imagined lasers in combat since the late 1960s, only the most modern laser systems are currently reaching what could be considered "experimental usefulness". In particular the Tactical High Energy Laser can be used in the anti-aircraft and anti-missile role. If current developments continue, some[who?] believe it is reasonable to suggest that lasers will play a major role in air defence starting in the next ten years.


Area air defence, the air defence of a specific area or location, (as opposed to point defence), have historically been operated by both armies (Anti-Aircraft Command in the British Army, for instance) and Air Forces (the United States Air Force's CIM-10 Bomarc). Area defence systems have medium to long range and can be made up of various other systems and networked into an area defence system (in which case it may be made up of several short range systems combined to effectively cover an area). An example of area defence is the defence of Saudi Arabia and Israel by MIM-104 Patriot missile batteries during the first Gulf War, where the objective was to cover populated areas.


The term air defence was probably first used by Britain when Air Defence of Great Britain (ADGB) was created as a Royal Air Force command in 1925. However, arrangements in the UK were also called 'anti-aircraft', abbreviated as AA, a term that remained in general use into the 1950s. After the First World War it was sometimes prefixed by 'Light' or 'Heavy' (LAA or HAA) to classify a type of gun or unit. Nicknames for anti-aircraft guns include AA, AAA or triple-A, an abbreviation of anti-aircraft artillery; "ack-ack" (from the spelling alphabet used by the British for voice transmission of "AA"); and archie (a World War I British term probably coined by Amyas Borton and believed to derive via the Royal Flying Corps from the music-hall comedian George Robey's line "Archibald, certainly not!").


The essence of air defence is to detect hostile aircraft and destroy them. The critical issue is to hit a target moving in three-dimensional space; an attack must not only match these three coordinates, but must do so at the time the target is at that position. This means that projectiles either have to be guided to hit the target, or aimed at the predicted position of the target at the time the projectile reaches it, taking into account speed and direction of both the target and the projectile.


Passive air defence is defined by NATO as "Passive measures taken for the physical defence and protection of personnel, essential installations and equipment in order to minimize the effectiveness of air and/or missile attack". It remains a vital activity by ground forces and includes camouflage and concealment to avoid detection by reconnaissance and attacking aircraft. Measures such as camouflaging important buildings were common in the Second World War. During the Cold War the runways and taxiways of some airfields were painted green.


The basic air defence unit is typically a battery with 2 to 12 guns or missile launchers and fire control elements. These batteries, particularly with guns, usually deploy in a small area, although batteries may be split; this is usual for some missile systems. SHORAD missile batteries often deploy across an area with individual launchers several kilometres apart. When MANPADS is operated by specialists, batteries may have several dozen teams deploying separately in small sections; self-propelled air defence guns may deploy in pairs.


The first issue was ammunition. Before the war it was recognised that ammunition needed to explode in the air. Both high explosive (HE) and shrapnel were used, mostly the former. Airburst fuses were either igniferious (based on a burning fuse) or mechanical (clockwork). Igniferious fuses were not well suited for anti-aircraft use. The fuse length was determined by time of flight, but the burning rate of the gunpowder was affected by altitude. The British pom-poms had only contact-fused ammunition. Zeppelins, being hydrogen filled balloons, were targets for incendiary shells and the British introduced these with airburst fuses, both shrapnel type-forward projection of incendiary 'pot' and base ejection of an incendiary stream. The British also fitted tracers to their shells for use at night. Smoke shells were also available for some AA guns, these bursts were used as targets during training.


Two assumptions underpinned the British approach to HAA fire; first, aimed fire was the primary method and this was enabled by predicting gun data from visually tracking the target and having its height. Second, that the target would maintain a steady course, speed and height. This HAA was to engage targets up to 24,000 feet. Mechanical, as opposed to igniferous, time fuses were required because the speed of powder burning varied with height so fuse length was not a simple function of time of flight. Automated fire ensured a constant rate of fire that made it easier to predict where each shell should be individually aimed.


The US ended World War I with two 3-inch AA guns and improvements were developed throughout the inter-war period. However, in 1924 work started on a new 105 mm static mounting AA gun, but only a few were produced by the mid-1930s because by this time work had started on the 90 mm AA gun, with mobile carriages and static mountings able to engage air, sea and ground targets. The M1 version was approved in 1940. During the 1920s there was some work on a 4.7-inch which lapsed, but revived in 1937, leading to a new gun in 1944.


In some countries, such as Britain and Germany during the Second World War, the Soviet Union and NATO's Allied Command Europe, ground based air defence and air defence aircraft have been under integrated command and control. However, while overall air defence may be for homeland defence including military facilities, forces in the field, wherever they are, invariably deploy their own air defence capability if there is an air threat. A surface-based air defence capability can also be deployed offensively to deny the use of airspace to an opponent.


After World War I the US Army started developing a dual-role (AA/ground) automatic 37 mm cannon, designed by John M. Browning. It was standardised in 1927 as the T9 AA cannon, but trials quickly revealed that it was worthless in the ground role. However, while the shell was a bit light (well under 2 lbs) it had a good effective ceiling and fired 125 rounds per minute; an AA carriage was developed and it entered service in 1939. The Browning 37mm proved prone to jamming, and was eventually replaced in AA units by the Bofors 40 mm. The Bofors had attracted attention from the US Navy, but none were acquired before 1939. Also, in 1931 the US Army worked on a mobile anti-aircraft machine mount on the back of a heavy truck having four .30 caliber water-cooled machine guns and an optical director. It proved unsuccessful and was abandoned.


Germany's high-altitude needs were originally going to be filled by a 75 mm gun from Krupp, designed in collaboration with their Swedish counterpart Bofors, but the specifications were later amended to require much higher performance. In response Krupp's engineers presented a new 88 mm design, the FlaK 36. First used in Spain during the Spanish Civil War, the gun proved to be one of the best anti-aircraft guns in the world, as well as particularly deadly against light, medium, and even early heavy tanks.


A plethora of anti-aircraft gun systems of smaller calibre were available to the German Wehrmacht combined forces, and among them the 1940-origin Flakvierling quadruple-20 mm-gun antiaircraft weapon system was one of the most often-seen weapons, seeing service on both land and sea. The similar Allied smaller-calibre air-defence weapons systems of the American forces were also quite capable, although they receive little attention. Their needs could cogently be met with smaller-calibre ordnance beyond using the usual singly-mounted M2 .50 caliber machine gun atop a tank's turret, as four of the ground-used "heavy barrel" (M2HB) guns were mounted together on the American Maxson firm's M45 Quadmount weapons system (as a direct answer to the Flakvierling),which were often mounted on the back of a half-track to form the Half Track, M16 GMC, Anti-Aircraft. Although of less power than Germany's 20 mm systems, the typical 4 or 5 combat batteries of an Army AAA battalion were often spread many kilometers apart from each other, rapidly attaching and detaching to larger ground combat units to provide welcome defence from enemy aircraft.


Another aspect of anti-aircraft defence was the use of barrage balloons to act as physical obstacle initially to bomber aircraft over cities and later for ground attack aircraft over the Normandy invasion fleets. The balloon, a simple blimp tethered to the ground, worked in two ways. Firstly, it and the steel cable were a danger to any aircraft that tried to fly among them. Secondly, to avoid the balloons, bombers had to fly at a higher altitude, which was more favorable for the guns. Barrage balloons were limited in application, and had minimal success at bringing down aircraft, being largely immobile and passive defences.


The maximum distance at which a gun or missile can engage an aircraft is an important figure. However, many different definitions are used but unless the same definition is used, performance of different guns or missiles cannot be compared. For AA guns only the ascending part of the trajectory can be usefully used. One term is 'ceiling', maximum ceiling being the height a projectile would reach if fired vertically, not practically useful in itself as few AA guns are able to fire vertically, and maximum fuse duration may be too short, but potentially useful as a standard to compare different weapons.


As this process continued, the missile found itself being used for more and more of the roles formerly filled by guns. First to go were the large weapons, replaced by equally large missile systems of much higher performance. Smaller missiles soon followed, eventually becoming small enough to be mounted on armored cars and tank chassis. These started replacing, or at least supplanting, similar gun-based SPAAG systems in the 1960s, and by the 1990s had replaced almost all such systems in modern armies. Man-portable missiles, MANPADs as they are known today, were introduced in the 1960s and have supplanted or even replaced even the smallest guns in most advanced armies.