A webcam cover is a physical solution that prevents the lens from capturing anything when you're not using it. The idea behind this type of cover is similar to what you would find on privacy eyeglasses, except much smaller in size. Most webcam covers fit over the lens and are made out of a variety of materials, such as plastic or metal. Some covers even come with adhesive so that they can be attached to your device. You can also find customizable covers that allow you to have your own design printed on them.