FPU): coprocessor that provides hardware routines for mathematical function, to be used with a CPU that does not have those functions built in. The 680x0 and 80x86 line of CPU chips had FPU chips available. Current CPUs (such as the PowerPC and the Pentium chips) incorporate floating point functions and do not need a separate FPU.
A floating point unit (FPU) is a part of a computer system specially designed to carry out operations on floating point numbers. Typical operations are addition, subtraction, multiplication, division, and square root. Some systems (particularly older, microcode-based architectures) can also perform various "transcendental" functions such as exponential or trigonometric calculations, though in most modern processors these are done with software library routines.