All true drums belong to the Membranophone family of instruments. They are instruments in which sound is made by the vibration of a stretched membrane or skin. They are classified on this website according to their body shapes.  Some instruments that are commonly called drums (i.e. steel drums, kettle drums) are made entirely of resonant solid material and would be classified as Idiophones.

     The Membranophone family of instruments consists of two basic groups: drums and mirlitons. Mirlitons are instruments that use a vibrating membrane to modify the sound made another way. Usually it is activated by blowing or singing against it. A Kazoo is an example of a Mirliton.

Drum categories are as follows:
          Cylindrical: Straight sided, with the same diameter throughout the drum.
          Conical: Sloping sides.
          Barrel: Bulging sides with both heads approximately equal in size.
          Waisted: An hourglass shaped drum.
          Goblet: Cup-like single headed drums made from wood or pottery.
          Footed: Single headed drums with legs that were cut from the body of the drum.
          Long: Elongated drums, usually made from a tree trunk.
          Vessel: A single membrane stretched over a pot or vessel.
          Frame: A membrane stretched over a thin wooden frame. Some have jingles attached.
          Friction: A membrane made to vibrate by rubbing with the fingers or damp cloth. Sometimes the head has a stick piercing the membrane.