The PARI system is a package which is capable of doing formal computations on recursive types at high speed. It is possible to use PARI in two different ways: 1) as a library, which can be called from any upper-level language application (for instance written in C, C++, Pascal or Fortran); 2) as a sophisticated programmable calculator, named GP, which contains most of the standard control instructions of a standard language like C. WWW: http://pari.math.u-bordeaux.fr/