FriCAS is an advanced computer algebra system. Its capabilities range from calculus (integration and differentiation) to abstract algebra. It can plot functions and has integrated help system.
FriCAS 1.2.1 builds on Linux and many Unix like systems (for example Mac OSX and Cygwin). FriCAS is build on top of Common Lisp; several Lisps can compile and run FriCAS -- currently supported are SBCL, ECL, Closure CL, Clisp, GCL.