Bit

A bit is a part of a horse bridle, and there are also tool bits.

In Computer science and information science, the word bit can have different meanings:

• A digit in binary notation, either 0 or 1. This is like a light switch; either there is light or there is not.
• A unit of measurement for the amount of data. This will be a multiple of 1 bit; only integers are allowed.
• As a unit of measurement for information. In this context, 1 bit is the amount of information that is present in the selection of two equally probable options. In this meaning, real values as multiples are possible.

When talking about storage space, 8 bits are usually called a byte.