The cello is a string instrument that belongs to the violin family. It is larger than a violin and viola, and it produces deeper, richer sounds. The cello has four strings tuned in perfect fifths, typically to C, G, D, and A. It is played while seated, with the instrument resting between the player's knees and supported by an endpin. Cellos are commonly used in various music genres, including classical, jazz, and contemporary music. They can be played solo or as part of an ensemble, such as a string quartet or orchestra. The instrument is known for its expressive range and ability to convey emotion.