What is PLC?

 A programmable logic controller (PLC) is an industrial computer that has been ruggedized and adapted for the control of manufacturing processes , including assembly lines, factory floors, material flow systems and more. Though previously this was a very centralized role that required programming in computer languages like PROLOG or ladder logic, modern PLCs have become much more accessible since the 1980s.

If you buy a popular system like Allen-Bradley's CompactLogix PLC from Rockwell Software, you can choose from 60+ programming languages to control these machines.