What are Embedded Systems?

Question: What are Embedded Systems?

An embedded system is a special-purpose system which performs a specific task with its own hardware. The embedded system is different from a general purpose computing devices (Like PC) because of its size, functionality and resources. Since the system is dedicated to specific tasks, design engineers can optimize it by reducing the size and cost of the product to a larger extent which requires good designing skills. Embedded systems are often mass-produced; in order to have cost savings multiplied by millions of items.
Physically, embedded systems range from portable consumer devices (such as MP3 players, PDA's, Mobile phones, gaming devices) to large Enterprise products (such as Enterprise routers, Networking switches and Industrial automation systems). From an engineering point of view embedded systems development is very different from an application development.

another Definition:

An embedded system is some combination of computer hardware and software, either fixed in capability or programmable, that is specifically designed for a particular kind of application device. Industrial machines, automobiles, medical equipment, cameras, household appliances, airplanes, vending machines, and toys (as well as the more obvious cellular phone and PDA) are among the myriad possible hosts of an embedded system. Embedded systems that are programmable are provided with a programming interface, and embedded systems programming is a specialized occupation.Usually a low power consumption CPU with a limited amount of memory is used in embedded Systems

Certain operating systems or language platforms are tailored for the embedded market, such as EmbeddedJava , Embedded C, Windows XP Embedded and Embedded Linux.
However, some low-end consumer products use very inexpensive microprocessors and limited storage, with the application and operating system both part of a single program. The program is written permanently into the system's memory in this case, rather than being loaded into RAM (random access memory) like programs on a personal computer.

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