From Freepedia
Taw or Tav is the twenty-second and last letter in many Semitic alphabets, including Phoenician, Hebrew, and Aramaic. The Phoenician letter gave rise to the Greek Tau (Τ), Latin T, and the equivalent in the Cyrillic alphabet.
The basic sound represented by the letter is an alveolar plosive: IPA [t], however in Hebrew it developed in certain cases (notably following a vowel within the same word) to a fricative sound: IPA [θ] — like English th in "thing", and this has further developed in certain dailects to [s]. When written with a dagesh (a dot in the middle of the letter) taw is pronounced [t]; when written without the dagesh, it is pronounced [θ], [s] or remains [t].
See also
Tav (number)
