In computing, a vector processor or array processor is a central processing unit (CPU) that implements an instruction set containing instructions that operate on
one-dimensional arrays of data called vectors, compared to scalar processors, whose instructions operate on single data items. Vector processors can greatly
improve performance on certain workloads, notably numerical simulation and similar tasks. Vector machines appeared in the early 1970s and dominated
supercomputer design through the 1970s into the 1990s, notably the various Cray platforms. The rapid fall in the price-to-performance ratio of conventional
microprocessor designs led to the vector supercomputer's demise in the later 1990s.
As of 2015 most commodity CPUs implement architectures that feature instructions for a form of vector processing on multiple (vectorized) data sets, typically
known as SIMD (Single Instruction, Multiple Data). Common examples include Intel x86's MMX, SSE and AVX instructions, Sparc's VIS extension, PowerPC's
AltiVec and MIPS' MSA. Vector processing techniques also operate in video-game console hardware and in graphics accelerators. In 2000, IBM, Toshiba and Sony
collaborated to create the Cell processor, consisting of one scalar processor and eight SIMD processors, which found use in the Sony PlayStation 3 among other
applications.
Other CPU designs may include some multiple instructions for vector processing on multiple (vectorised) data sets, typically known as MIMD (Multiple Instruction,
Multiple Data) and realized with VLIW. Such designs are usually dedicated to a particular application and not commonly marketed for general-purpose computing.
The Fujitsu FR-V VLIW/vector processor combines both technologies.