A sequence of adjacent bits operated on as a unit by a computer. A byte usually consists of eight bits. Amounts of computer memory are often expressed in terms of megabytes (1,048,576 bytes) or gigabytes (1,073,741,824 bytes).
Our Living Language : The word bit is short for binary digit. A bit consists of one of two values, usually 0 or 1. Computers use bits because their system of counting is based on two options: switches on a microchip that are either on or off. Thus, a computer counts to seven in bits as follows: 0, 1, 10 , 11 , 100 , 101 , 110 , 111 . Notice that the higher the count, the more adjacent bits are needed to represent the number. For example, it requires two adjacent bits to count from 0 to 3, and it takes three adjacent bits to count from 0 to 7. A sequence of bits can represent not just numbers but other kinds of data, such as the letters and symbols on a keyboard. The sequence of 0s and 1s that make up data are usually counted in groups of 8, and these groups of 8 bits are called bytes. The word byte is short for binary digit eight. To transmit one keystroke on a typical keyboard requires one byte of information (or 8 bits). To transmit a three-letter word requires three bytes of information (or 24 bits).