[[File:International Morse Code.svg|thumb|upright=1.2|Chart of the Morse code 26 letters and 10 numerals<ref name=ITU-R-M-1677/>]]
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'''Morse code''' is a [[telecommunications]] method which [[Character encoding|encodes]] [[Written language|text]] characters as standardized sequences of two different signal durations, called ''dots'' and ''dashes'', or ''dits'' and ''dahs''.<ref name=Beechey-1876/><ref name=Camm-1941/> Morse code is named after [[Samuel Morse]], one of several developers of the code system. Morse's preliminary proposal for aan [[electrical telegraph]] code was repacedreplaced by [[Alfred Vail]], and Vail's was later adopted for commercial [[American Morse code|commercial electrical telegraph]]ytelegraphy in North America]]. Another, substantial developer was [[Friedrich Clemens Gerke|Friedrich Gerke]] who effectively streamlined Vail's designencoding to produce the telegraph codeencoding adopted in Europe; most of the alphabetic part of the current international ([[International Telecommunications Union|ITU]]) "Morse" code was copied over from Gerke's revision.
'''International Morse code''' encodes the 26 [[ISO basic Latin alphabet|basic Latin letters]] '''{{sc|A}}''' to '''{{sc|Z}}''', one [[diacritic|accented]] Latin letter ('''{{sc|É}}'''), the [[Indo-Arabic numerals]] '''{{math|0}}''' through '''{{math|9}}''', and a small set of punctuation and messaging procedural signals ([[Prosignsprosigns for Morse code|prosigns]]). There is no distinction between upper and lower case letters.<ref name=ITU-R-M-1677/> Each Morse code symbol is formed by a sequence of ''dits'' and ''dahs''. The ''dit'' duration can vary for signal clarity and operator skill, but for any one message, once the [[rhythm]] is established, a [[beat (music)|half-beat]] is the basic unit of time measurement in Morse code. The duration of a ''dah'' is three times the duration of a ''dit'' (although some telegraphers deliberately exaggerate the length of a ''dah'' for clearer signalling). Each ''dit'' or ''dah'' within an encoded character is followed by a period of signal absence, called a ''space'', equal to the ''dit'' duration. The letters of a word are [[Delimiter|separated by]] a space of duration equal to three ''dits'', and words are separated by a space equal to seven ''dits''.<ref name=ITU-R-M-1677/><ref name=TR-Paris-1949>{{cite report |title=Telegraph Regulations |orig-year=1947 |year=1949 |series=ITU History |place=Geneva, CH |publisher=[[International Telecommunication Union]] |url=https://search.itu.int/history/HistoryDigitalCollectionDocLibrary/1.36.48.en.100.pdf |page=42 |quote=the space between two words is equal to seven dots;}} — Annexed to the ''International Telecommunication Convention'', Atlantic City, 1947; revised Paris, 1949.</ref>{{efn|
Until 1949, words were separated by a space equal to five ''dits''.<ref name=TR-Cairo-1938>{{cite report |title=Telegraph Regulations |orig-year=1932 |year=1938 |series=ITU History |place=Geneva, CH |publisher=[[International Telecommunication Union]] |url=https://search.itu.int/history/HistoryDigitalCollectionDocLibrary/1.35.48.en.100.pdf#search=morse%201938 |page=39 |quote=The space between two words is equal to five dots.}} — Annexed to the ''International Telecommunication Convention'', Madrid, 1932; revised Cairo, 1938.</ref>
