Real-time computing
In computer science,
real-time computing, or
reactive computing, is the study of hardware and software systems that are subject to a "real-time constraint", for example operational deadlines from event to system response. Real-time programs must guarantee response within strict time constraints, often referred to as "deadlines". Real-time responses are often understood to be in the order of milliseconds, and sometimes microseconds. Conversely, a system without real-time facilities, cannot
guarantee a response within any timeframe. A real-time system is one which "controls an environment by receiving data, processing them, and returning the results sufficiently quickly to affect the environment at that time." The use of this word should not be confused with the two other legitimate uses of "real-time". In the domain of simulations, the term means that the simulation's clock runs as fast as a real clock. In the processing and enterprise systems domains, the term is used to mean "without perceivable delay".