computing Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It includes the study and experimentation of algorithmic processes, and development of both hardware and software. Computing has scientific, ...

, single instruction stream, single data stream (SISD) is a computer architecture in which a single uni-core processor executes a single instruction stream, to operate on data stored in a single memory. This corresponds to the

von Neumann architecture The von Neumann architecture — also known as the von Neumann model or Princeton architecture — is a computer architecture based on a 1945 description by John von Neumann, and by others, in the '' First Draft of a Report on the EDVAC''. Th ...

. SISD is one of the four main classifications as defined in

Flynn's taxonomy Flynn's taxonomy is a classification of computer architectures, proposed by Michael J. Flynn in 1966 and extended in 1972. The classification system has stuck, and it has been used as a tool in design of modern processors and their functionalities ...

. In this system, classifications are based upon the number of concurrent instructions and data streams present in the computer architecture. According to Michael J. Flynn, SISD can have concurrent processing characteristics. Pipelined processors and

superscalar processor A superscalar processor is a CPU that implements a form of parallelism called instruction-level parallelism within a single processor. In contrast to a scalar processor, which can execute at most one single instruction per clock cycle, a su ...

s are common examples found in most modern SISD computers.Ibaroudene, Djaffer. Chapter 1: Motivation and History, ''Parallel Processing''. St. Mary's University, San Antonio, TX. Spring 2008. Instructions are sent to the control unit from the memory module and are decoded and sent to the processing unit which processes on the data retrieved from memory module and sends back to it.

References

{{compu-hardware-stub Flynn's taxonomy SISD