What are screws?
A screw is a common fastener whose function is to join two or more objects together. The structure of the screw is very simple, usually composed of two parts: the head and the thread. The head has different shapes, such as groove, cross, hexagonal, etc., for tightening or loosening with the corresponding screwdriver or wrench. The screw thread is a helical bulge along the screw shaft, which is used to insert the hole of the connected object to form a firm fix.
The invention of screws dates back to ancient Greece, when they were used to make spiral-like pumps and mechanical devices. With the arrival of the industrial revolution, the production and application of screws have been greatly developed, and have become indispensable parts in various machinery, electronics, construction, furniture and other fields. Modern screws have a variety of different materials, specifications, performance and functions to meet different needs and occasions.
Although the screw may seem insignificant, it carries an important mission. It is a symbol of connection and unity, a tool for creativity and innovation, a witness to civilization and progress. Without screws, many great inventions and buildings would not have been possible.