A power adapter is a device that converts electrical energy from one form to another, allowing electronic devices to receive the appropriate voltage and current. They are commonly used to charge devices like smartphones, laptops, and tablets. Power adapters can be found in various shapes and sizes, depending on the device they are designed to support. Most power adapters consist of a transformer, which changes the voltage, and a rectifier, which converts alternating current (AC) to direct current (DC). Some adapters also include additional features like overcurrent protection and short-circuit protection to ensure the safety of both the device and the user.