J

J is the tenth letter in the modern English alphabet and the ISO basic Latin alphabet. Its normal name in English is jay /ˈdʒeɪ/ or, now uncommonly, jy /ˈdʒaɪ/. When used for the palatal approximant, it may be called yod (/ˈjɒd/ or /ˈjoʊd/) or yot (/ˈjɒt/ or /ˈjoʊt/).

The letter 'J' originated as a swash letter i, used for the letter 'I' at the end of Roman numerals when following another 'i', as in 'xxiij' instead of 'xxiii' for the Roman numeral representing 23. A distinctive usage emerged in Middle High German.Gian Giorgio Trissino (1478–1550) was the first to explicitly distinguish I and J as representing separate sounds, in his Ɛpistola del Trissino de le lettere nuωvamente aggiunte ne la lingua italiana ("Trissino's epistle about the letters recently added in the Italian language") of 1524. Originally, 'I' and 'J' were different shapes for the same letter, both equally representing /i/, /iː/, and /j/; but, Romance languages developed new sounds (from former /j/ and /ɡ/) that came to be represented as 'I' and 'J'; therefore, English J, acquired from the French J, has a sound value quite different from /j/ (which represents the initial sound in the English word "yet").

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