A solenoid valve is an electromechanical device used to control the flow of liquids or gases in a system. It consists of a coil of wire, known as a solenoid, that generates a magnetic field when electricity passes through it. This magnetic field moves a plunger or armature, opening or closing the valve to regulate flow. These valves are commonly used in various applications, including irrigation systems, automotive fuel systems, and industrial automation. They are valued for their reliability, quick response time, and ability to be controlled remotely, making them essential components in many modern systems.