This document summarizes several common musical instruments from the string, keyboard, brass, and percussion families. It notes that the violin is the most popular string instrument, while the viola is similar but slightly larger with a lower sound. The cello must be held between the knees to play. The double bass stands over six feet tall and is the lowest string instrument. The harp is described as the instrument of the angels with 47 strings and seven pedals. The piano is the most popular keyboard instrument. The guitar is usually played with fingers or a pick. The trumpet is the most popular brass instrument and one of the oldest. The trombone can slide between notes. The tuba is the lowest brass instrument. The organ