Drum skins are commonly known as drum heads and refer to the membrane stretched across one or both open ends of a drum. When you hit this drum skin with a drumstick or your hands, it makes a sound because the membrane vibrates and the sound echoes through the drum. Up until the invention of a drumhead made of plastic in 1956 animal skin was the material used for this membrane. Not only are the plastic drumheads cheaper, they also last longer and do not wear as easily as those made from animal skin.
There are occasions, however, where the traditional drum heads are still used, such as in historical reenactments, so that the audience gets the full effect of the sound of the drums. Kevlar, or aramid fiber, is another material used in making drum skins. This fiber is even more durable than plastic or animal skin and is most often found in the large drums used in marching bands. This is because of the way in which the drummer has to hit both sides of the drum.
In order for the drum skin to attach to the shell of the drum, other components are needed. The hoop or rim of the drum can be made of metal, wood or other materials. Screws or bolts pass through this rim to hold the drumhead in place. These bolts also serve as a tuning device for the drumhead. To tune the drum you loosen or tighten the bolts and this affects the sound the drum skin makes when you hit it. Some drums are very loud, so drummers use mufflers, such as specific types of heads or even foam and pillow to help reduce the loudness of the drum.