Morse code most common letter in English, the letter "E", has the shortest code: a single dot. Because the Morse code elements are specified by proportion rather than specific time durations, the code is usually transmitted at the highest rate that the receiver is capable of decoding. The Morse code transmission rate ("speed") is specified in "groups per minute", commonly referred to as "words per minute". Morse code is usually transmitted by on-off keying of an information carrying medium such as electric current, radio waves, visible light or sound waves. The current or wave is present during time period of the dot
History of the International Phonetic Alphabet History of the International Phonetic Alphabet The International Phonetic Alphabet was created soon after the International Phonetic Association was established in the late 19th century. It was intended as an international system of phonetic transcription for oral languages, originally for pedagogical purposes. The Association was established in Paris in 1886 by French and British language teachers led by Paul Passy. The prototype of the alphabet appeared in . The Association based their alphabet upon the Romic alphabet of Henry Sweet, which in turn was based on the Phonotypic Alphabet of Isaac Pitman and the Palæotype of Alexander John Ellis. The