Milling-cutter Tools and End-mill

End mills are the most common milling cutters. End mills are available in a wide variety of lengths, diameters, and types. A square end mill is used for most general milling applications. It produces a sharp edge at the bottom of pockets and slots.
End mills can be center cutting and non-center cutting. As their name implies, center cutting end mills have cutting edges on both the end face of the cutter and the sides. Center cutting end mills are essential for plunge milling.
Non-center cutting end mills have cutting edges only on the sides and are used only for side milling. These tools are identified by a small hole at the center.