Screw / Nuts / Bolts - A screw is a shaft with a helical groove or thread formed on its surface and provision at one end to turn the screw. It is used to fasten objects together, and as a simple machine used to translate torque into linear force.
Nuts are fasteners that are designed to fit around and secure a bolt or screw. Bolts are threaded rods or pins that are used to fasten objects together. They usually have a head at one end and a thread at the other.