T, or t, is the twentieth letter in the modern English alphabet and the ISO basic Latin alphabet. Its name in English is tee (pronounced ), plural tees.[1] It is derived from the Semitic letters taw (ת, ܬ, ت) via the Greek letter τ (tau). In English, it is most commonly used to represent the voiceless alveolar plosive, a sound it also denotes in the International Phonetic Alphabet. It is the most commonly used consonant and the second most common letter in English-language texts.[2]

Taw was the last letter of the Western Semitic and Hebrew alphabets. The sound value of Semitic Taw, Greek alphabet Tαυ (Tau), Old Italic and Latin T has remained fairly constant, representing [t] in each of these; and it has also kept its original basic shape in most of these alphabets.

In English, ⟨t⟩ usually denotes the voiceless alveolar plosive (International Phonetic Alphabet and X-SAMPA: /t/), as in tart, tee, or ties, often with aspiration at the beginnings of words or before stressed vowels.

The digraph ⟨ti⟩ often corresponds to the sound /ʃ/ (a voiceless palato-alveolar sibilant) word-medially when followed by a vowel, as in nation, ratio, negotiation, and Croatia.

The letter ⟨t⟩ corresponds to the affricate /t͡ʃ/ in some words as a result of yod-coalescence (for example, in words ending in "-ture", such as future).

A common digraph is ⟨th⟩, which usually represents a dental fricative, but occasionally represents /t/ (as in Thomas and thyme.)

In the orthographies of other languages, ⟨t⟩ is often used for /t/, the voiceless dental plosive /t̪/, or similar sounds.

In the International Phonetic Alphabet, ⟨t⟩ denotes the voiceless alveolar plosive.

Also for encodings based on ASCII, including the DOS, Windows, ISO-8859 and Macintosh families of encodings.