<storage> A fundamental unit of storage in a computer. The size of a word in a particular computer architecture is one of its chief distinguishing characteristics.
The size of a word is usually the same as the width of the computer's data bus so it is possible to read or write a word in a single operation. An instruction is usually one or more words long and a word can be used to hold a whole number of characters. These days, this nearly always means a whole number of bytes (eight bits), most often 32 or 64 bits. In the past when six bit character sets were used, a word might be a multiple of six bits, e.g. 24 bits (four characters) in the ICL 1900 series.