The tau cross is a T-shaped cross, sometimes with all three ends of the cross expanded. It is called a "tau cross" because it is shaped like the Greek letter tau, which in its upper-case form has the same appearance as the Latin letter T.
Another name for the same object is Saint Anthony's cross or Saint Anthony cross, a name given to it because of its association with Saint Anthony of Egypt.
The Christian cross, seen as symbolizing the crucifixion of Jesus, is a symbol of Christianity. It is related to the crucifix, a cross that includes a corpus (a representation of Jesus's body, usually three-dimensional) and to the more general family of cross symbols. The term cross is now detached from its original specifically Christian meaning, in modern English and many other Western languages.
The basic forms of the cross are the Latin cross with unequal arms and the Greek cross with equal arms; there are numerous variants, partly with confessional significance - such as the tau cross, the double-barred cross, triple-barred cross, and cross-and-crosslets - and many heraldic variants, such as the cross potent, cross pattée, and cross moline, cross fleury.