Beowulf is a design for high-performance parallel computing clusters on inexpensive personal computer hardware. Originally developed by Donald Becker at NASA, Beowulf systems are now deployed worldwide, chiefly in support of scientific computing.
A Beowulf cluster is a group of usually identical PC computers running Linux or another open source Unix operating system, such as FreeBSD. They are networked together into a small TCP/IP LAN, and have libraries and programs installed which allow processing to be shared among them.
There is no particular piece of software that defines a cluster as a Beowulf. Commonly used parallel processing libraries include MPI (Message Passing Interface) and PVM (Parallel Virtual Machine). Both of these permit the programmer to divide up a task among a group of networked computers, and recollect the results of processing.
The name comes from the legend of Beowulf.