GiNaC is a free computer algebra system released under the GNU General Public License. The name is a recursive acronym for "GiNaC is Not a CAS" (Computer Algebra System). This is similar to the GNU acronym "GNU is not Unix".What distinguishes GiNaC from most other computer algebra systems is that it does not provide a high-level interface for user interaction. Rather, it encourages its users to write symbolic algorithms directly in C++, which is GiNaC's implementation programming language.