A bolt is a form of threaded fastener with an external male thread. Bolts are very closely related . Further information: List of screw drives. Bolts use a wide.
A nut is a type of fastener with a threaded hole. Nuts are almost always used in conjunction with a mating bolt to fasten multiple parts together.
A screw is a type of fastener, in some ways similar to a bolt, typically made of metal, and characterized by a helical ridge, known as a male thread.