embedded system is a special-purpose computer system,
which is completely encapsulated by the device it controls.
An embedded system has specific requirements and performs
pre-defined tasks, unlike a general-purpose personal
computer. An embedded system is a programmed hardware
device. A programmable hardware chip is the 'raw material'
and it is programmed with particular applications. This is
to be understood in comparison to older systems with full
functional hardware or systems with general purpose hardware
and externally loaded software. Embedded systems are a
combination of hardware and software which facilitates mass
production and variety of application.