What are the function of drilling machine?

There are many advantages, mainly concerning the amount of different tools you can use in them. The bench drill press can take bits of up to 1/2 shank size and many of those are drill bits up to an inch wide. ( it's quite common to have large drills with reduced shanks) -Other items like large hole saws can be used, as well as 'fly cutters', which are cutting bits on the end of a movable beam. These can usually cut holes in thin materials like plexiglass sheet, up to a foot in diameter. Forstner bits up to 6 or 8 inch can be used, these cut large, flat bottomed holes for installing clocks and other instruments. Milling bits can be used to 'mill' large areas of rough surface to smoothness, and 'square hole tools' can also be used. The large drill press is a very versatile tool.