Percussion instruments, played by either being struck or shaken, include members that are the oldest instruments in the world. Different types of drums, for example, have been in existence for thousands of years. Two principal divisions exist in the percussion family: the untuned instruments like the bass drum and the timpani that produce a sound when struck but no specific definite tone; and the tuned instruments like the xylophone, the bells, and the triangle, which have a recognizable pitch.

   Most of the instruments are made of either wood or metal. Drums have stretched animal skin fitted over the metal or wooden frame that, depending on the tension of the skin, produces a deep resonant tone. In general, percussion instruments act as the rhythm section of the orchestra. The snare drum has skin over both ends, creating a rattling sound. Most percussion instruments were used for military purposes (to call men into action) until the 17th century when composers began using them in their works. Beethoven was one of the first to integrate them wholeheartedly into his symphonies.

    Other untuned percussion instruments that are normally used in orchestras include the cymbal and the gong, both of which are mainly used at climactic moments in the musical score. The sweet, high pitch sounds of tuned instruments like the bells have normally been used in orchestras to add a 'celestial' motif to the compositions.