nibble

In computing, a nibble (often nybble or even nyble to match the vowels of byte) is a four-bit aggregation, or half an octet. As a nibble contains 4 bits, there are sixteen (24) possible values. A nibble can be represented by a single hexadecimal digit and called a “hex digit” or, less commonly, a “hexit”. A full byte (octet) is represented by two hexadecimal digits; therefore, it is common to display a byte of information as two nibbles. The nibble is often called a “semioctet” or a “quartet” in a networking or telecommunication context. Sometimes the set of all 256 byte values is represented as a table 16×16, which gives easily readable hexadecimal codes for each value.