A genre is a category of an art form. The word is used of subsets of literature, films, television shows, and music that fit certain criteria. Often a work will fit into one genre, but it is possible for a work to have multiple genres. The term music genre is used to refer to a variety of facets of music, including the period during which a musical composition was written, its style, its instrumentation and treatment of those instruments, its form and function, its means of transmission, its means of dissemination, and the location of its geographical origins sometimes crossed with the cultural or ethnic background of the composer. There is no agreement or a single comprehensive system to talk about music genre at the present time.

People may refer to some or all of a small group of categories when using period as the criteria for a music genre. These include Early Music, Medieval Music, Renaissance Music, Baroque Music, Classical Music, Romantic Music, and Twentieth Century Music. The definitions of these music periods are open to interpretation. For example, is the Classical period from 1730 to 1820? Or is it from 1750 to 1830? Or did it start in the late 18th century? All of these interpretations are current today.

Works like concertos, which have a featured solo instrument highlighted against an orchestral background, and duets, which have only two instruments, fall into the category of instrumentation and treatment of instruments as music genre, as do the designations “orchestral music” or “percussion ensemble music.” Opera is another genre of this type, featuring voices and orchestra, as is a cappella music, which depends on unaccompanied voices.

“Popular music” is a music genre based on period and means of transmission, as are “traditional music” and “folk music.” “Native American music” and “South African music” are both music genre terms that speak to geography and culture. And marches, lullabies, minuets, and other music named for dances have to do with a combination of form and function.

Possibly the clearest cut set of definitions of music genres is found in award situations. The Grammy Awards is an example. In this context, although one finds music genres based on a variety of criteria—for example, “Alternative” is based on what the music is not; “Children’s” is based on the audience; “Musical Show” is based on form; etc.—the music genre criteria are applied consistently and over time, so that a tradition of definition is built up.

Some of the music genres that are popular today include jazz, hip-hop, rap, rock, rhythm and blues, pop. Many people have eclectic tastes in music, and people still perform, view, purchase, and enjoy a wide range of music, including show tunes, folk music, classical music, opera, and ballet music.