A ball valve is a type of valve that controls the flow of liquids or gases through a pipe. It consists of a hollow, perforated sphere, or ball, that rotates within the valve body. When the ball is turned so that the hole is aligned with the pipe, the flow is allowed; when it is turned perpendicular, the flow is blocked. This design allows for quick and easy operation. Ball valves are commonly used in various applications, including plumbing, industrial processes, and oil and gas systems. They are favored for their durability, reliability, and ability to provide a tight seal, making them suitable for both high-pressure and low-pressure environments.