A computer word is a unit of data that has defined length expressed in bits. The bit length of a computer word typically corresponds to the width of the computer's data bus, which allows a single CPU operation to move it from storage to processor register.
In computer environments that utilize eight-bit bytes, a computer word is a multiple of eight. For example, in Intel’s CPU architecture, a word consists of two connected eight-bit bytes, while in IBM’s System/360 architecture, it features four eight-bit bytes. Computer words normally contain application data, storage address or computer instructions. Depending on the processor architecture they use, some computers support half-, double-, and quad-words. The length of a computer word is directly proportional to the amount of work a processor can perform in a single operation.