Programmable logic controller (PLC)
A programmable logic controller (PLC), sometimes called as programmable controller, is an industrial computer used to monitor inputs, and depending upon their state make decisions based on its program or logic, to control (turn on/off) its outputs to automate a machine or a process. That means the programmable logic controller (PLC) is used for automation of electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or lighting fixtures.
Programmable logic controllers (PLCs, programmable controllers) are used in many industries and machines. The programmable logic controller (PLC) is not like the general-purpose computer, is used for automation. It's designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed or non-volatile memory. A programmable logic controller (PLC) is one kind of a real time system since output results must be produced in response to input conditions within a limited time, otherwise unintended operation will result.
