Answer 1

It is an integrated circuit that controls one or more processes. You can refer to an Arduino type that can be programmed for several things, for example, robotics

Answer 2

It is a processor with memory and on chip devices, which perform a specific task. Example: washing machine, Airconditioner uses a microcontroller

Answer 3

A bit like a small computer (CPU and memory) used for a specific purpose.

Answer 4

google this!