An optocoupler is an optical transmitter-receiver assembly in which the electrical signal is converted into light and emitted, and on the other hand, a sensor converts the light back into an electrical signal. An optocoupler consists of an optical transmitter or emitter, an LED, and a light-sensitive receiver. The receiver can be a photodiode, phototransistor, photoresistor, SCR or optical thyristor (photothyristor) or optical triac (phototriac). Optocouplers are used to switch larger electronic components such as transistors and triacs in isolation between a low voltage control signal (such as an Arduino or microcontroller) and a high voltage main current output signal. Common applications of optocouplers include input/output switching of microprocessors, control DC and AC power, computer communications, signal isolation, and power source regulation are noted to have problems with ground current loops.