An embedded system is a computer system designed to perform dedicated functions. It is embedded as part of a complete device including hardware and mechanical parts. Embedded systems control many devices in common use today, like cameras, mp3 players, cell phones etc. Embedded systems are controlled by one or more main processing cores (ICs) that is usually a micro-controller or a digital signal processor (DSP).
Comparing an embedded system with a general-purpose personal computer, a PC is designed to be flexible and to meet a wide range of end-user needs, like playing games, browsing etc. But an embedded system is dedicated to specific tasks only, like in a calculator, set-top box, mobile phones etc. Since they are dedicated for specific tasks, design engineers can optimize it reducing the size and cost of the product and increasing the reliability and performance. Some embedded systems are mass-produced, like mobile phones and calculators.
Physically, embedded systems range from portable devices such as digital watches and MP3 players, to large stationary installations like traffic lights, factory controllers, or the systems controlling nuclear power plants. Complexity varies from low, with a single micro-controller chip, to very high with multiple units, peripherals and networks mounted inside a large chassis or enclosure.
