A Programmable Logic Controller (PLC) is generally defined as a tiny industrial computer that contains both hardware and software. More specifically, PLCs will be used to automate industrial electromechanical processes, such as machinery control on factory assembly lines, amusement rides, or food processing.
They are designed for a variety of arrangements with extended temperature range, resistance to electrical noise, and resistance to vibration and shock.
A PLC consists of two basic parts: a central processing unit (CPU) and an input/output (I/O) interface system.