A branch circuit is a part of an electrical system that distributes power from the main service panel to various outlets, lights, and appliances within a building. It consists of conductors, circuit breakers, and other components that ensure safe and efficient operation. Each branch circuit is designed to handle a specific load, preventing overloads and potential hazards. Branch circuits can be classified into different types, such as lighting circuits and receptacle circuits. They are essential for providing electricity to different areas of a home or building, allowing for the use of multiple devices simultaneously without compromising safety or performance.