Dictionary.net

Hardware and software which forms a component ofsome larger system and which is expected to function withouthuman intervention.A typical embedded system consists of a single-boardmicrocomputer with software in ROM, which starts runningsome special purpose application program as soon as it isturned on and will not stop until it is turned off (if ever).An embedded system may include some kind of operating systembut often it will be simple enough to be written as a singleprogram. It will not usually have any of the normalperipherals such as a keyboard, monitor, serial connections,mass storage, etc. or any kind of user interface softwareunless these are required by the overall system of which it isa part. Often it must provide real-time response.Usenet newsgroup: news:comp.arch.embedded.