Screw You use screws every single day — you just don’t notice them. They’re inside your phone, furniture, motorcycles, cars, computers, door locks, home appliances, factory machines, medical instruments…Small as they are, without screws, the world simply cannot be assembled, cannot operate, and cannot be repaired. This article will help you understand screws quickly — their functions, materials, and where they are used. --- 1. What is a screw and why is it important? A screw