The harp is different from the other stringed instruments. It's tall, about six feet, shaped a little like the number 7, and has 47 strings of varying lengths, which are tuned to the notes of the white keys of the piano. There are usually one or two harps in an orchestra and they play both melody and harmony. You play the harp sitting down with your legs on either side, with the neck of the harp leaning on your right shoulder. Each string sounds a different note (they come in different colors to help you tell one from another) and you play them by plucking the strings with your fingertips and thumb. Attached to the bottom of the harp are seven foot pedals, which change the pitch of each string and allow them to sound the pitches of the black keys on the piano.