The viola is a string instrument that is bowed or played with varying techniques. It is slightly larger than a violin and has a lower and deeper sound. Since the 18th century, it has been the middle or alto voice of the violin family, between the violin (which is tuned a perfect fifth above) and the cello (which is tuned an octave below). The strings from low to high are typically tuned to C3, G3, D4, and A4.
In the past, the viola varied in size and style as did its names. The word viola originates from Italian. The Italians often used the term: “viola da braccio” meaning literally: ‘of the arm’. “Brazzo” was another Italian word for the viola, which the Germans adopted as Bratsche. The French had their own names: cinquiesme was a small viola, haute contre was a large viola, and taile was a tenor. Today, the French use the term alto, a reference to its range.
The viola was popular in the heyday of five-part harmony, up until the eighteenth century, taking three lines of the harmony and occasionally playing the melody line. Music for the viola differs from most other instruments in that it primarily uses the alto clef. When viola music has substantial sections in a higher register, it switches to the treble clef to make it easier to read.