What are the differences between microprocessor , microcontroller and plc ?

A microprocessor and a microcontroller are both chips while a PLC is a complete system

A microprocessor needs external memory- and I/O-chips, while these are integated in a microcontroller

A PLC consists of at a printed circuitboard, a microprocessor or a microcontroller, and interface circuits

It Means the microprocessor or a microcontroller is a part of PLC

Microprocessor is a combination of CPU,Control Unit,I/O devices while a Microcontroller is a combination of Microprocessor and Storing element and PlC is a system of varios microcontroller and other devices.

Practically Microcontroller is a complete system with built in RAM and ROM. You only need to apply the opcodes or bit handling commands and utilize the I/Os as required, while microprocessor doesnot have bult in RAM or ROM. External RAMS or ROMS are required to installed along with microprocessor.

On the other hand, Microcontroller is used where your task is dedicated and you have to perform that task continuously. If you have to perform multiple tasks then microprocessor will be used.

Microcontroller has few opcodes with more bit operations while microprocessor has more opcodes for few bit operations.

Pcb micro controller used to input number of pins to observe maximum output.

A plc is a system (sometimes refered to as a embedded system or it can be a piece of software running on a PC) that uses a microprocessor or microcontroller as one of the componentsA microcontroller is a general term and can mean different things to different people and manufacturers use it as they feel fit. Often it depends on the context its used in.

The difference between microcontroller and microprocessor is that, microprocessor is a multiple integrated central processing unit which can process, save and display data through output. It is a multipurpose device. While, microcontroller is a single circuit small device containing memory, processor core and an output unit. It is used for single purpose and in small applications. PLC is a multi input and output digital computers used to control factory machine lines and heavy applications.