A Byte is a unit of storage capable of holding a single character. A byte is made up of 8 bits.

Byte - Abbreviation for "binary term".
Large amounts of memory are indicated in terms of kilobytes (1,024 bytes), megabytes (1,048,576 bytes), and gigabytes (1,073,741,824 bytes).

Also see Terabyte, Petabyte, Exabyte, Zettabyte, and Yottabyte.