Abstract
Message Passing Interface (MPI) allows a group of computers in a network to be specified as a cluster system. It provides the routines for task activation and communication. Writing programs for a cluster system is a difficult job. In this paper the Message-passing Interface is presented. Parallel programs using the WMPI, a version of MPI, to solve the pi(π) calculation the quick sort algorithm and the Torsion problem are presented. The programs are written and compiled in Microsoft Visual C+ +.