A ball peen hammer is a type of hand tool commonly used in metalworking and construction. It features a flat striking surface on one end and a rounded, ball-shaped end on the other. The flat side is used for driving nails and shaping metal, while the rounded side is ideal for peening, which is the process of shaping or compressing metal surfaces. This hammer is typically made of steel and comes in various sizes. It is an essential tool for tasks such as blacksmithing, machining, and sheet metal work, where precision and control are important.