Calc is arbitrary precision arithmetic system that uses a C-like
language. Calc is useful as a calculator, an algorithm prototyper and
as a mathematical research tool. More importantly, calc provides one
with a machine independent means of computation. Calc comes with a
rich set of builtin mathematical and programmatic functions. A
partial list of calc builtin functions is available.

The calc language is a C-like language. The language includes
commands such as variable declarations, expressions, tests, labels,
loops, file operations, function calls. These commands are very
similar to their counterparts in C.