A washer is a thin, flat, disc-shaped component with a hole in the center, used in conjunction with a bolt, nut, or screw to distribute load, reduce friction, and prevent loosening. Washers come in various shapes, sizes, and materials, depending on their application. They play a crucial role in mechanical assemblies by protecting surfaces from damage and improving the efficiency of fastening systems. Washers can also provide locking mechanisms to secure connections, absorb vibrations, and compensate for misalignments. There are several types of washers, each designed for specific functions in industries such as automotive, construction, aerospace, and machinery.