Programmable Logic Controllers (PLCs) were developed to automate industrial processes and machinery, replacing control systems based on relays, timers, and complex wiring. They are found in production lines, transportation systems, machines, and even building installations, receiving signals from sensors, processing information according to an internal program, and controlling actuators (motors, valves, cylinders, etc.). Features such as the number of inputs/outputs, processing capacity, and others are listed in this guide to help you choose the product best suited to your project requirements.