A diode rectifier is an electronic component that converts alternating current (AC) into direct current (DC). It uses one or more diodes, which are semiconductor devices that allow current to flow in only one direction. This process is essential for powering electronic devices that require a stable DC supply. In a typical setup, the diode rectifier is connected to an AC power source. When the AC voltage changes polarity, the diode only allows the positive half of the waveform to pass through, effectively blocking the negative half. This results in a pulsating DC output, which can be smoothed further using filters for more stable power delivery.