In today's world, embedded systems are everywhere -- homes, offices, cars, factories, hospitals, plans and consumer electronics. Their huge numbers and new complexity call for a new design approach, one that emphasizes high-level tools and hardware/software tradeoffs, rather than low-level assembly-language programming and logic design.
In general, "embedded system" is not an exactly defined term, as many systems have some element of programmability. For example, Handheld computers

Embedded systems span all aspects of modern life and examples of their use is numerous.

Telecommunications systems employ numerous embedded systems from telephone switches for the network to mobile phones at the end-user. Computer networking uses dedicated routers and network bridges to route data.