The definition of an embedded system, in the simplest of terms, would be a blend of hardware that is controlled and operated via a specifically designed software to accomplish a particular task.
Embedded systems are most likely to dedicated to serving a particular purpose. Examples of embedded systems are: mobile phones, gadgets, scientific and medical instruments, large-scale industries and machinery including automobile and agriculture, and a range of other appliances.
Some embedded systems do not have a user interface (UI). Others, which are commonly used in mobile devices and computerized equipment come with a graphical user interface (GUI), or LEDs, touchscreen sensors, and even physical buttons.
A typical Embedded System comprises three primary components: hardware, software and real-time operating system (RTOS). It is the operating system that enables the hardware and the software to interact and determine the functionality of the system as a whole.
Embedded Systems can be considered as the real-time control systems which are based on a microcontroller and are driven by a specially designed software. Such a blend of technology makes these systems highly valuable for small- and large-scale applications.