Power rectifiers are different than general purpose diodes in that they are larger and have more current carrying capabilities. They have many uses but are found more commonly in DC power supplies or direct current power transmission systems. A single diode will provide half-wave rectification of a AC signal. The resulting waveform is considered pulsating DC. The diodes here would be useful for inverters, switch-mode power supplies, linear power supplies, converters and ultrasonic systems etc.