The viola is a string instrument that is slightly larger than a violin and has a deeper, richer sound. It typically has four strings tuned to C, G, D, and A, which are a fifth lower than those of the violin. The viola is played with a bow and is commonly used in orchestras, chamber music, and solo performances. Violas are made from wood, often featuring a carved body that enhances their acoustic properties. The instrument is known for its warm tone and is an essential part of the string family, contributing to the harmony and texture of musical compositions.