Computer Algebra System
A computer algebra system (CAS) is a computer program that helps people with mathematics and algebra. It manipulates mathematical equations and expressions containing numbers and symbols called variables, which stand for known or unknown values that can be solved for, or replaced with any value.
Computer algebra systems can be special purpose, focusing on only a few types of symbolic math, to very large, general purpose programs that do almost everything (like Mathematica).
Modern computer algebra systems often include extensive numeric capabilities for convenience and which fit together with its symbolic abilities. Numeric domains supported typically include real, complex, interval, rational, and algebraic numbers. Usually floating point arithmetic is available to use if desired, because the arithmetic is done by most computer hardware very quickly.