An inverter and a rectifier perform opposite functions in electronic circuits. Both act as electric power converters; a rectifier changes current from alternating current (AC) to direct current (DC), while an inverter converts DC to AC.
A rectifier takes power from an AC source (like a home outlet) and converts it to DC, usually of a lower voltage. Radios, television receivers and power tools commonly contain rectifiers.
Rectifiers come in two basic types: half-wave and full-wave. A half-wave rectifier allows electricity of only one polarity (positive or negative) to pass through, while a full-wave rectifier permits both. Electronic components called diodes form the heart of rectifier circuits, as they pass current in only one direction. A half-wave rectifier may have one or two diodes; a full-wave rectifier requires four.
An inverter transforms a low voltage DC current (such as 9 or 12 volts) to a high voltage AC current. For example, when camping, you might use an inverter to power 120-volt AC appliances from your car's 12-volt battery. Converting DC to AC is more complicated than AC to DC; an inverter is a very complex and expensive circuit compared to a rectifier, which typically has only a few simple parts.