Systems that have some or all components embedded into the computing process instead of being separate — usually achieved with a single circuit board. Use this tag for questions about small, single-board devices.
The term embedded systems covers a very wide range of computing systems, technologies, and devices.
In terms of computer hardware, one of the most popular embedded systems is the Raspberry Pi since all of its essential components (CPU, RAM, etc.) are part of the circuit board itself (hence the term single-board PC).