Tera

Tera (symbol: T) is a prefix in the SI system of units denoting 10¹², or 1,000,000,000,000.

In computer science tera can sometimes mean 1,099,511,627,776 (2⁴⁰), instead of 1,000,000,000,000, especially when used to prefix the byte, giving a terabyte. See binary prefix.