This character is a Other Letter and is mainly used in the Arabic script.
The glyph is not a composition. It has no designated width in East Asian texts. In bidirectional text it is written as Arabic letter from right to left. When changing direction it is not mirrored. The word that U+0629 forms with similar adjacent characters prevents a line break inside it. The glyph can be confused with 5 other glyphs.
The Wikipedia has the following information about this codepoint:
Taw, tav, or taf is the twenty-second and last letter of the Semitic abjads, including Phoenician tāw 𐤕, Hebrew tav ת, Aramaic taw 𐡕, Syriac taw ܬ, and Arabic tāʾ ت (22nd in abjadi order, 3rd in modern order). In Arabic, it also gives rise to the derived letter ثṯāʾ. Its original sound value is /t/.
The Phoenician letter gave rise to the Greek tau (Τ), Latin T, and Cyrillic Т.