A ball end mill is a type of cutting tool used in milling machines to create rounded shapes and contours in materials like metal, wood, and plastic. Its design features a hemispherical end, which allows it to produce smooth, curved surfaces and intricate details. Ball end mills are commonly used in applications such as 3D machining, mold making, and die manufacturing. These tools come in various sizes and can be made from different materials, including high-speed steel and carbide. The choice of a specific ball end mill depends on factors like the material being machined, the desired finish, and the machining speed.