MPICH is a high performance and widely portable implementation of the Message Passing Interface (MPI) standard.
The goals of MPICH are: (1) to provide an MPI implementation that efficiently supports different computation and communication platforms including commodity clusters (desktop systems, shared-memory systems, multicore architectures), high-speed networks (10 Gigabit Ethernet, InfiniBand, Myrinet, Quadrics) and proprietary high-end computing systems (Blue Gene, Cray) and (2) to enable cutting-edge research in MPI through an easy-to-extend modular framework for other derived implementations.
MPICH is distributed as source (with an open-source, freely available license). It has been tested on several platforms, including Linux (on IA32 and x86-64), Mac OS/X (PowerPC and Intel), Solaris (32- and 64-bit), and Windows.