Page "Central processing unit" Paragraph 31

Related to number representation is the size and precision of numbers that a CPU can represent.

In the case of a binary CPU, a bit refers to one significant place in the numbers a CPU deals with.

The number of bits ( or numeral places ) a CPU uses to represent numbers is often called " word size ", " bit width ", " data path width ", or " integer precision " when dealing with strictly integer numbers ( as opposed to floating point ).

This number differs between architectures, and often within different parts of the very same CPU.

For example, an 8-bit CPU deals with a range of numbers that can be represented by eight binary digits ( each digit having two possible values ), that is, 2 < sup > 8 </ sup > or 256 discrete numbers.

In effect, integer size sets a hardware limit on the range of integers the software run by the CPU can utilize.