An embedded system can be defined as a computer system designed to perform specific functions. This generally goes with real-time computing constraints. Embedded systems bring together software, hardware and mechanical parts with either fixed or programmable capabilities.  

Embedded systems are very specific, and built to handle a particular task. The processing cores are crucial for the working of any Embedded system. These processing cores are either microcontrollers or digital signal processors (DSP). The possible hosts of an Embedded system are industrial machines, automobiles, airplanes, trains, medical equipment, video cameras, phones, PDAs, home appliances, vending machines and toys.

The role of the design engineers is not only to optimize and reduce the size of the product, but also to enhance its reliability and performance.  Embedded systems may be for specialized use, or for mass use; in the earlier the production aims to meet the need, and in the later it is usually mass production for the consumer market.

Modern day's electronics and electronic gadgets are but Embedded systems that make things convenient and comfortable for users in the day to day life. Embedded systems are deployed in controlling traffic lights, factory controllers, or nuclear power plants.

The complexity of an Embedded system varies from device to device. There may be devices that are dependent on single microcontroller chip, and also devices with multiple units, peripherals and networks. Notably, a device may or may be dependent solely on an Embedded system. It may include the working of an Embedded system along with an operating system and microprocessors.