Relay
A relay is an electrically operated switch that uses an electromagnet to mechanically open or close electrical contacts, allowing a low-power control circuit to control a high-power load circuit. It provides electrical isolation between the control and load circuits, protecting sensitive components from high voltages or currents. Relays are fundamental components in automation, control systems, and power management applications.
Developers should learn about relays when working on embedded systems, IoT devices, or hardware projects that require switching high-power loads (e.g., motors, lights, or appliances) using low-power microcontrollers like Arduino or Raspberry Pi. They are essential for implementing safety features, such as overload protection, and for creating automated control systems in industrial, automotive, or home automation contexts.