Message Passing Interface (MPI)

MPI provides source-code portability of message-passing programs written in C or Fortran across a variety of architectures.

Just as for the sequential case, this has many benefits, including protecting investment in a program, allowing development of the code on one architecture (e.g. a network of workstations) before running it on the target machine (e.g. fast specialist parallel hardware)

Basic concept of processes communicating by sending messages to one another has been understood for a number of years, it is only relatively recently that message-passing systems have been developed which allow source-code portability.