There are many different types of screws for different purposes. They differ in terms of thread type, thread pitch, thread form, screw head shape and screw drive. The most common screws are:
Machine screws– For driving screws in metal parts.
Tapping screws– For joining metal plates up to twelve millimetres.
Self-drilling screws– For joining steel, aluminium and other non-ferrous metal plates.
Drywall screws– For joining plastics, wood, plasterboard and aluminium.
Wood screws– For driving screws in wood parts.
Chipboard screws– For fixing chipboard.