Western classical music most commonly refers to the formal, as distinct from popular and folk, music tradition of the Western world from the Medieval (500–1400), Renaissance (1400–1600), Baroque (1600–1750), Classical (1750–1820) and Romantic (1800–1910) eras. Often, although not entirely without controversy, the Modernist (1890–1975) and Contemporary (1950–present) periods are also included.
A distinguishing feature of Western classical music is the use of staff notation to indicate to the performer the pitches and durations for notes. Another is the use of often complex and highly sophisticated orchestration that can weave together melody, harmony, rhythm, counterpoint, development, texture, and form. Major genres of Western classical music include symphony, concerto, opera, ballet, tone poem, mass, chamber music, and instrumental solo.