Electronic device power supplies are known as PSUs. Power adapters plug into a wall socket and change AC current into a single DC voltage. They are sometimes known as “AC adapters” or “chargers.” The power adapter is the external component of the power supply for a laptop. Computers require various DC voltages.
An AC adapter, AC/DC adapter, or AC/DC converter is a type of external power supply, often enclosed in a case
similar to an AC plug. Other common names include wall wart, power brick, wall charger, and power adapter.
Adapters for battery-powered equipment may be described as chargers or rechargers (see also battery charger).
AC adapters are used with electrical devices that require power but do not contain internal components to derive
the required voltage and power from mains power. The internal circuitry of an external power supply is very similar
to the design that would be used for a built-in or internal supply