A Programmable Logic Controller (PLC) is an industrial digital computer designed to control manufacturing processes or machinery. It uses programmable software to automate tasks, making it essential in various industries like automotive, food processing, and packaging. PLCs can monitor inputs from sensors and make decisions based on pre-set conditions to manage outputs like motors and valves. PLCs are known for their reliability and flexibility, allowing for easy reprogramming as production needs change. They typically feature a modular design, enabling users to add or remove components as necessary. This adaptability helps businesses improve efficiency and reduce downtime in their operations.