A phone charger is a device used to supply electrical energy to a mobile phone's battery. It typically consists of a power adapter that plugs into an electrical outlet and a cable that connects to the phone. The charger converts alternating current (AC) from the outlet into direct current (DC) suitable for charging the phone. Most phone chargers come with different connectors, such as USB-C or Lightning, to fit various phone models. They can vary in charging speed, with some offering fast charging capabilities. Using the correct charger is important to ensure safe and efficient charging of the device.