This document is a presentation about power supplies. It begins by stating that power supplies are one of the most used electronic equipment in the world today. It then explains that a power supply can broadly be defined as anything that supplies power, such as dams or an internal combustion engine. The presentation goes on to discuss what a power supply is, its technical details, and applications of power supplies. It notes that it will look at different types of power supplies, how they operate, and examples of their uses.