A power supply is a critical device that provides electrical energy to power electronic circuits and systems. It converts electrical energy from a source, such as mains electricity or batteries, into a suitable voltage and current for various applications. Power supplies can be categorized into linear and switching types, each offering distinct advantages in efficiency and regulation. They are widely used in industrial equipment, consumer electronics, and telecommunications, ensuring stable and reliable operation. With features like overload protection, voltage regulation, and energy efficiency, power supplies are essential for maintaining the functionality and safety of electronic devices and systems.