Bit
Sometimes abbreviated as b, a bit is short for binary digit and is a single unit of information that can have a value of either ON or OFF. Eight bits make up a byte, as shown in the picture to the right.
When working with colors and trying to determine the amount of colors in a bit color depth, this can be calculated by: 2 to the power of the bit color. In other words, an 8-bit color would be 2^8 = 256 colors.
Also see: BER, Binary, Bitrate, Check bits, Hard drive definitions, Qubit, Measurement, Nibble, Parity bit, Start bit, Stop bit