Novices in electronics usually think that the microcontroller is the same as the microprocessor. That's not true. They differ from each other in many ways. The first and most important difference in favour of the microcontroller is its functionality. In order for the microprocessor to be used, other components, first of all memory, must be added to it. Even though it is considered a powerful computing machine, it is not capable of establishing direct communication with the peripherals. Instead, specialized circuits must be used for this purpose. This is how it was in the beginning and remains the same today.