A quartet is a musical composition or performance involving four musicians or singers. This format is commonly found in various genres, including classical, jazz, and contemporary music. In classical music, a string quartet typically consists of two violins, a viola, and a cello, while vocal quartets may feature four singers harmonizing together. Quartets can also refer to the group of four performers themselves. Famous examples include the Beethoven String Quartet and the King's Singers, known for their vocal harmonies. Quartets allow for intricate interplay between the musicians, creating rich textures and dynamic performances.