Massive parallelism is a term used in computer architecture, reconfigurable computing, application-specific integrated circuit (ASIC) and field-programmable gate array (FPGA) design. It signifies the presence of several (many) independent arithmetic units, that run in parallel. Early examples of such a system are the Distributed Array Processor, the Goodyear MPP, and the Connection Machine.
Today's most powerful supercomputers are all MPP systems such as Earth Simulator, Blue Gene, ASCI White, ASCI Red, ASCI Purple, ASCI Thor's Hammer.
In this class of computing, all of the processing elements are connected together to be one very large computer. This is in contrast to distributed computing where massive numbers of separate computers are used to solve a single problem.