What is difference between bolt & screw?

What is the difference between a screw and a bolt?

• Answer:

  Screws have threads and bolts sometimes do and sometimes don't have threads. Screws join things together, wood or metal or plastic. Bolts have a nut on the other end and may use washers or spacers. Bolts need a hole drilled for them, a screw may not if it is self tapping. Bolts hold the material and usually compress it. Screws are held by the material and are usually compressed by it. Bolts have / use nuts or some sort of a compatible threaded interface. Screws are compression fit into or thru and held tight by a material like wood, metal, plastic or bone (perish the thought). The term screw and bolt are often used interchangeably. It is the same hardware - just a different application. Technically, a screw is assembled into a tapped hole and torqued at the head. A bolt is inserted through a clearance hole and fastened by a nut. It is tightened by torque on the nut. what is the difference Between Screw & Bolts.