toilet. a chemical toilet collects human excreta in a holding tank and uses chemicals to minimize odors. they do not require a connection to a water supply and are used in a variety of situations. these toilets are usually, but not always, self-contained and movable. a chemical toilet is structured around a relatively small tank, which needs to be emptied frequently. it is not connected to a hole in the ground (like a pit latrine), nor to a septic tank, nor is it plumbed into a municipal system leading to a sewage treatment plant. when the tank is emptied, the contents are usually pumped into a sanitary sewer or directly to a treatment plant. the portable toilets used on construction sites and at large gatherings such as music festivals are well-known types of chemical toilet. as they are usually used for short periods and because of their high prices, they are mostly rented rather than bought, often including servicing and cleaning. a simpler type of chemical toilet may be used in travel trailers (caravans) and on small boats. toilet fed to animals the pig toilet, which consists of a toilet linked to a pigsty by a chute, is still in use to a limited extent. it was common in rural china, and was known in japan, korea, and india. the "fish pond toilet" depends on the same principle, of livestock (often carp) eating human excreta directly. "flying toilet" this section is an excerpt from flying toilet. a flying toilet is a facetious name for a plastic bag that is used as a simple collection device for human faeces when there is a lack of proper toilets and people are forced to practise open defecation. the filled and tied plastic bags are then discarded in ditches or on the roadside. associated especially with slums, they are called flying toilets "because when you have filled them, you throw them as far away as you can". squat toilets this section is an excerpt from squat toilet. a squat toilet (or squatting toilet) is a toilet used by squatting, rather than sitting. this means that the posture for defecation and for female urination is to place one foot on each side of the toilet drain or hole and to squat over it. there are several types of squat toilets, but they all consist essentially of a toilet pan or bowl at floor level. such a toilet pan is also called a "squatting pan". a squat toilet may use a water seal and therefore be a flush toilet, or it can be without a water seal and therefore be a dry toilet. the term "squat" refers only to the expected defecation posture and not any other aspects of toilet technology, such as whether it is water flushed or not. at topkapı palace, turkey old-style squat toilet (hong kong) in france porcelain squat toilet with water tank for flushing (wuhan, china) japanese-style squat toilet with automatic sensor usage urination main article: urination a man seen from behind urinating while standing. there are cultural differences in socially accepted and preferred voiding positions for urination around the world: in the middle east and asia, the squatting position is more prevalent, while in the western world the standing and sitting position are more common. anal cleansing habits main article: anal cleansing a modern bidet of the traditional type, available in many southern european and south american countries. in the western world, the most common method of cleaning the anal area after defecation is by toilet paper or sometimes by using a bidet. in many muslim countries, the facilities are designed to enable people to follow islamic toilet etiquette qaḍāʼ al-ḥājah. for example, a bidet shower may be plumbed in. the left hand is used for cleansing, for which reason that hand is considered impolite or polluted in many asian countries. the use of water in many christian countries is due in part to the biblical toilet etiquette which encourages washing after all instances of defecation. the bidet is common in predominantly catholic countries where water is considered essential for anal cleansing, and in some traditionally orthodox and lutheran countries such as greece and finland respectively, where bidet showers are common. there are toilets on the market where the seats have integrated spray mechanisms for anal and genital water sprays (see for example toilets in japan). this can be useful for the elderly or people with disabilities. accessible toilets main article: accessible toilet an accessible toilet is designed to accommodate people with physical disabilities, such as age related limited mobility or inability to walk due to impairments. additional measures to add toilet accessibility are providing more space and grab bars to ease transfer to and from the toilet seat, including enough room for a caregiver if necessary. public toilets this section is an excerpt from public toilet. a public toilet, restroom, public bathroom or washroom is a room or small building with toilets (or urinals) and sinks for use by the general public. the facilities are available to customers, travelers, employees of a business, school pupils and prisoners and are commonly separated into male and female toilets, although some are unisex, especially for small or single-occupancy public toilets. public health aspects further information: wash § health aspects to this day, 1 billion people in developing countries have no toilets in their homes and are resorting to open defecation instead. therefore, it is one of the targets of sustainable development goal 6 to provide toilets (sanitation services) to everyone by 2030. toilets are one important element of a sanitation system, although other elements are also needed: transport, treatment, disposal, or reuse. diseases, including cholera, which still affects some 3 million people each year, can be largely prevented when effective sanitation and water treatment prevents fecal matter from contaminating waterways, groundwater, and drinking water supplies. history further information: history of water supply and sanitation ancient history sewage and toilet structures in the city of lothal of the indus river valley in around 2350 bc. roman public toilets, ostia antica. model of toilet with pigsty, china, eastern han dynasty 25–220 ad the fourth millennium bc would witness the invention of clay pipes, sewers, and toilets, in mesopotamia, with the city of uruk today exhibiting the earliest known internal pit toilet, from c. 3200 bc. the neolithic village of skara brae contains examples, c. 3000 bc, of internal small rooms over a communal drain, rather than pit. the indus valley civilisation in northwestern india and pakistan was home to the world's first known urban sanitation systems. in mohenjo-daro (c. 2800 bc), toilets were built into the outer walls of homes. these toilets had vertical chutes, via which waste was disposed of into cesspits or street drains. in the indus city of lothal (c. 2350 bc), houses belonging to the upper class had private toilets connected to a covered sewer network constructed of brickwork held together with a gypsum-based mortar that emptied either into the surrounding water bodies or alternatively into cesspits, the latter of which were regularly emptied and cleaned. other very early toilets that used flowing water to remove the waste are found at skara brae in orkney, scotland, which was occupied from about 3100 bc until 2500 bc. some of the houses there have a drain running directly beneath them, and some of these had a cubicle over the drain. around the 18th century bc, toilets started to appear in minoan crete, pharaonic egypt, and ancient persia. in 2012, archaeologists found what is believed to be southeast asia's earliest latrine during the excavation of a neolithic village in the rạch núi archaeological site, southern vietnam. the toilet, dating back 1500 bc, yielded important clues about early southeast asian society. more than 30 coprolites, containing fish and shattered animal bones, provided information on the diet of humans and dogs, and on the types of parasites each had to contend with. in roman civilization, latrines using flowing water were sometimes part of public bath houses. roman latrines, like the ones pictured here, are commonly thought to have been used in the sitting position. the roman toilets were probably elevated to raise them above open sewers which were periodically "flushed" with flowing water, rather than elevated for sitting. romans and greeks also used chamber pots, which they brought to meals and drinking sessions. johan j. mattelaer said, "plinius has described how there were large receptacles in the streets of cities such as rome and pompeii into which chamber pots of urine were emptied. the urine was then collected by fullers." (fulling was a vital step in textile manufacture.) the han dynasty in china two thousand years ago used pig toilets. post-classical history garderobes were toilets used in the post-classical history, most commonly found in upper-class dwellings. essentially, they were flat pieces of wood or stone spanning from one wall to the other, with one or more holes to sit on. these were above chutes or pipes that discharged outside the castle or manor house. garderobes would be placed in areas away from bedrooms to shun the smell and also near kitchens or fireplaces to keep the enclosure warm. garderobe seat openings view looking down into garderobe seat opening exterior view of garderobe at campen castle toilet in rosenborg castle copenhagen the other main way of handling toilet needs was the chamber pot, a receptacle, usually of ceramic or metal, into which one would excrete waste. this method was used for hundreds of years; shapes, sizes, and decorative variations changed throughout the centuries. chamber pots were in common use in europe from ancient times, even being taken to the middle east by medieval pilgrims. modern history bourdaloue chamber pots from the austrian imperial household early 18th century british three-seat privy 19th century thunderbox, a heavy wooden commode to enclose chamber pot by the early modern era, chamber pots were frequently made of china or copper and could include elaborate decoration. they were emptied into the gutter of the street nearest to the home. in pre-modern denmark, people generally defecated on farmland or other places where the human waste could be collected as fertilizer. the old norse language had several terms for referring to outhouses, including garðhús (yard house), náð-/náða-hús (house of rest), and annat hús (the other house). in general, toilets were functionally non-existent in rural denmark until the 18th century. by the 16th century, cesspits and cesspools were increasingly dug into the ground near houses in europe as a means of collecting waste, as urban populations grew and street gutters became blocked with the larger volume of human waste. rain was no longer sufficient to wash away waste from the gutters. a pipe connected the latrine to the cesspool, and sometimes a small amount of water washed waste through. cesspools were cleaned out by tradesmen, known in english as gong farmers, who pumped out liquid waste, then shovelled out the solid waste and collected it during the night. this solid waste, euphemistically known as nightsoil, was sold as fertilizer for agricultural production (similarly to the closing-the-loop approach of ecological sanitation). in the early 19th century, public officials and public hygiene experts studied and debated sanitation for several decades. the construction of an underground network of pipes to carry away solid and liquid waste was only begun in the mid 19th-century, gradually replacing the cesspool system, although cesspools were still in use in some parts of paris into the 20th century. even london, at that time the world's largest city, did not require indoor toilets in its building codes until after the first world war. the water closet, with its origins in tudor times, started to assume its currently known form, with an overhead cistern, s-bends, soil pipes and valves around 1770. this was the work of alexander cumming and joseph bramah. water closets only started to be moved from outside to inside of the home around 1850. the integral water closet started to be built into middle-class homes in the 1860s and 1870s, firstly on the principal bedroom floor and in larger houses in the maids' accommodation, and by 1900 a further one in the hallway. a toilet would also be placed outside the back door of the kitchen for use by gardeners and other outside staff such as those working with the