Coil springs are mechanical devices made from coiled metal that store and release energy. They are commonly used in various applications, such as in vehicles, furniture, and machinery, to absorb shocks and support weight. When a force is applied, the coil compresses or stretches, allowing it to return to its original shape when the force is removed. These springs come in different sizes and materials, depending on their intended use. For example, in automobiles, coil springs help provide a smooth ride by absorbing bumps in the road. In furniture, they enhance comfort by allowing cushions to flex and support the body.