The term became current in the 1980s as a marketing/classificatory device in the media and the music industry, and it is generally used to classify any kind of "foreign" (i.e. non-Western) music.
In musical terms, "world music" can be roughly defined as music which uses distinctive ethnic scales, modes and musical inflections, and which is usually (though not always) performed on or accompanied by distinctive traditional ethnic instruments, such as the kora (West African lute), the steel drum, the sitar or the didgeridoo.
World music is, most generally, all the music in the world.[2] More specifically, the term is currently used to classify the many genres of non-Western music which were previously described as "folk music" or "ethnic music". However, "world music" does not have to mean traditional folk music, it may refer to the indigenous classical forms of various regions of the world, and to modern, cutting edge pop music styles as well. Succinctly, it can be described as "local music from out there",[3] or "someone else's local music".[4]
Music from around the world exerts wide cross-cultural influence as styles naturally influence one another, and in recent years "world music" has also been marketed as a successful genre in itself. Academic study of world music, as well as the musical genres and individual artists with which it has been associated, can be found in such disciplines as anthropology, Folkloristics, Performance Studies and ethnomusicology.
Examples of popular forms of world music include the various forms of non-European classical music (e.g. Japanese koto music, Hindustani raga music, Tibetan chants), eastern European folk music (e.g. the village music of Bulgaria) and the many forms of folk and tribal music of the Middle East, Africa, Asia, Oceania and Central and South America.
The broad category of "world music" includes isolated forms of ethnic music from diverse geographical regions. These dissimilar strains of ethnic music are commonly categorized together by virtue of their indigenous roots. Over the 20th century, the invention of sound recording, low-cost international air travel and common access to global communication among artists and the general public has given rise to a related phenomenon called "cross-over" music. Musicians from diverse cultures and locations could readily access recorded music from around the world, see and hear visiting musicians from other cultures and visit other countries to play their own music, creating a melting pot of stylistic influences.
While communication technology allows greater access to obscure forms of music, the pressures of commercialisation also present the risk of increasing musical homogeny, the blurring of regional identities, and the gradual extinction of traditional local music-making practices.

[edit] Popular non-Western genres
Although it primarily describes traditional music, the world music genre also includes popular music from non-Western urban communities (e.g. South African "township" music) and non-European music forms that have been influenced by other "third world" musics (e.g. Afro-Cuban music), although Western-style popular song sourced from non-English-speaking countries in Western Europe (e.g. French pop music) would not generally be considered world music.