A microcontroller is a computer on a single chip that’s limited in functionality and usually embedded in another device. You will find microcontrollers in coffee makers, automobiles, mobile phones and many other devices. Some microcontrollers are pre-programmed to do something specific, like control the mechanics of a coffee maker. Others can be programmed by users to perform a custom set of activities. A microcontroller usually has input and output. The input pins might be data that’s read from a sensor, such as a temperature or motion sensor. The output pins might drive a motor or turn on a lamp. Microcontrollers are often the brains in a robot. A robot might have more than one microcontroller that controls a different part of its body or a different function.
The Arduino was one of the first microcontrollers sold to hobbyists. The Arduino is open-source hardware, which means its designs are freely available to anyone. For this reason, there are many different types of Arduinos available on the market. Some have simply been cloned from the original design, and others have features that improve upon the design or emphasize a particular function or feature to create a more specialized device. Microcontrollers are at the heart of the Maker movement.