Screw
By:Jeff Perkins and Bryece Dawson
The screws function
Screws Are used to join together objects that need to be put together
Machine screw
They might be considered a screw or a bolt based on the distinction. In practice, they tend to be mostly available in smaller sizes and the smaller sizes are referred to as screws or less ambiguously as machine screws, although some kinds of machine screw can be referred to as stove bolts.
Other types of screws
Lag screw
. A typical lag bolt can range in diameters from 1/4" to 1 1/4", and lengths from 1/4" to 6" or longer, with coarse threads of a wood-screw or sheet-metal-screw threadform (but larger). The head is typically an external hex. The materials are usually carbon steel substrate with a coating of zinc