From this point of view, all machines are divided into 4 groups:
General purpose machines (broadly generic) - screw-cutting lathes, vertical and horizontal milling, vertical and radial drilling, cylindrical grinding etc.
General purpose machines with enhanced performance - a turret lathe, automatic lathes and semi-automatic, longitudinal - and vertical turning and milling, buscentre-grinding, etc. (less versatile, have a smaller range of rotation frequencies and feeds).
Machines for a specific purpose (special) - gear cutting, gear hobbing, turning, copying, etc. (for operations of the same name, a certain type of parts).
Special machine — to perform only one operation in a single technological process. Special machines are divided into two types: special and ordinary aggregate.
The most widely used aggregation for machine tools drilling and boring groups.