Microcontrollers

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A Microcontroller (MCU, μC) is a small computer system on a single chip. But its resources and capabilities such as memory, speed, external interfaces are very much limited than of a desktop computer because the MCU targets embedded applications.

A typical microcontroller includes:
 - Processor
 - Volatile memory
 - Non-volatile memory
 - Input/Output (I/O) pins
 - Peripherals
 - Clock
 - Bus interfaces

All on a single chip.

This is also why a microcontrollers is usually called a System on Chip.