You will find people use interchangeably these three words: Microprocessor, Microcomputer and Microcomputer. But these are completely different entities and you must be very clear about the difference of Microprocessor, Microcontroller and Microcomputer. Well, let me help you to clarify these three terms in simple language.
Microprocessor: Microprocessor is a simple central processing unit (CPU) on a single chip (remember the word ‘Single Chip’). It includes Arithmetic logic unit (ALU), control unit (CU), registers, instruction decoders, bus control circuit etc. but everything should be on a single chip.
Microcomputer: A microcomputer is the association of microprocessor and the peripheral I/O devices, support circuitry and memory (both data and program). It is not necessary to be on a single chip (remember this point, not in a single chip).
Microcontroller: The last one, microcontroller is similar to microcomputer but all the components like I/O peripherals and memory should be on a single chip. (so everything should be on a single chip).
Now I think you must be clear about the distinction of these three terms: Microprocessor, Microcomputer and Microcontroller. Please share your ideas about the difference of microcontroller, microprocessor and microcomputer and also give comment on this.