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 ## What is an Embedded System?
 
-[Analog Devices](https://www.analog.com/en/design-center/glossary/embedded-system.html): An embedded system is a system in which the **computer** (generally a microcontroller or microprocessor) is included as an integral part of the system. Often, the computer is relatively **invisible to the user**, without obvious applications, files, or operating systems. Examples of products with invisible embedded systems are the controller that runs a microwave oven or the engine control system of a modern automobile.
+[Making Embedded Systems](https://www.oreilly.com/library/view/making-embedded-systems/9781449308889/): An embedded system is a **computerized system** that is **purpose built** for its application.
 
-[Wikipedia](https://en.wikipedia.org/wiki/Embedded_system): An embedded system is a **computer system**—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function **within a larger mechanical or electronic system**.
+[Analog Devices](https://www.analog.com/en/design-center/glossary/embedded-system.html): An embedded system is a system in which the **computer** (generally a microcontroller or microprocessor) is included as an integral part of the system. Often, the computer is relatively **invisible to the user**, without obvious applications, files, or operating systems. Examples of products with invisible embedded systems are the controller that runs a microwave oven or the engine control system of a modern automobile.
 
 [Embedded Systems Glossary](https://barrgroup.com/embedded-systems/glossary-e): A combination of **computer hardware and software**, and perhaps **additional mechanical or other parts**, designed to perform a **dedicated function**. In some cases, embedded systems are **part of a larger system** or product, as in the case of an antilock braking system in a car.