TRIACsTRIACs (triode for alternating current) are a type of thyristor, which is a type of electronic device that is used to control the flow of current in a circuit. TRIACs are commonly used in AC power control applications, such as in dimmer switches for lights or in motor speed control systems. Unlike a traditional switch, which can only turn the current on or off, a TRIAC can control the amount of current flowing through the circuit, allowing for precise control of AC power.