The Tamil script (தமிழ் அரிச்சுவடி tamiḻ ariccuvaṭi "Tamil alphabet") is a script that is used to write the Tamil language as well as other minority languages such as Badaga, Irula, and Paniya. With the use of diacritics to represent aspirated and voiced consonants not represented in the basic script, it is also used to write Saurashtra and, by Tamils, to write Sanskrit.

The Tamil script has 12 vowels (உயிரெழுத்து uyireḻuttu "soul-letters"), 18 consonants (மெய்யெழுத்து meyyeḻuttu "body-letters") and one character, the āytam ஃ (ஆய்தம்), which is classified in Tamil grammar as being neither a consonant nor a vowel (அலியெழுத்து aliyeḻuttu "the hermaphrodite letter"), though often considered as part of the vowel set (உயிரெழுத்துக்கள் uyireḻuttukkaḷ "vowel class"). The script, however, is syllabic and not alphabetic. The complete script, therefore, consists of the thirty-one letters in their independent form, and an additional 216 combinant letters representing a total 247 combinations (உயிர்மெய்யெழுத்து uyirmeyyeḻuttu) of a consonant and a vowel, a mute consonant, or a vowel alone. These combinant letters are formed by adding a vowel marker to the consonant. Some vowels require the basic shape of the consonant to be altered in a way that is specific to that vowel. Others are written by adding a vowel-specific suffix to the consonant, yet others a prefix, and finally some vowels require adding both a prefix and a suffix to the consonant. In every case the vowel marker is different from the standalone character for the vowel.