Viola da braccio in the context of "Gaudenzio Ferrari"

The viola da gamba (Italian: [ˈvjɔːla da (ɡ)ˈɡamba, viˈɔːla -]), or viol, or informally gamba, is a bowed and fretted string instrument that is played da gamba (i.e. "on the leg"). It is distinct from the later violin, or viola da braccio; and it is any one of the earlier viol family of bowed, fretted, and stringed instruments with hollow wooden bodies and pegboxes where the tension on the strings can be increased or decreased to adjust the pitch of each of the strings. Although treble, tenor and bass were most commonly used, viols came in different sizes, including pardessus (high treble, developed in 18th century), treble, alto, small tenor, tenor, bass and contrabass (called violone).

These members of the viol family are distinguished from later bowed string instruments, such as the violin family, by both appearance and orientation when played—as typically the neck is oriented upwards and the rounded bottom downwards to settle on the lap or between the knees.

The viola (/viˈoʊlə/ vee-OH-lə, () Italian: [ˈvjɔːla, viˈɔːla]) is a string instrument of the violin family, and is usually bowed when played. Violas are slightly larger than violins, and have a lower 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 higher) and the cello (which is tuned an octave lower). 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 the Italian language. 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.