What is world music, and why does it exist?

The term World music became current in the 1980s as a marketing/ classificatory device in the media and music industry.World music is Israeli reggae, it's rock and roll from the Sahara and flamenco with a hip-hop breakbeat; it's cowboy music from Venezuela and Persian classical music from L.A. It's music that transcends borders.
In our interconnected world a great song can come out of anywhere: crossing oceans and continents, and leveling barriers of race, religion, nationality, class and even language. This is the essence of what's become known as world music: it's the soundtrack of globalization, and the sound of the world we live in today.
Music transcends categories, too, and there's no fixed definition for world music. It's a slippery term - as changeable and varied as the music it attempts to describe. To some, world music is field recordings and ethnographic music, for others it's simply pop music from somewhere else. Many consider world music a marketing concept and a catchall for the various international sounds that aren't easily categorized; while many more consider it an alternative to the mainstream. All of these definitions are correct: World music contains multitudes.
When discussing world music we have to ask ourselves how are these categories established. upon what terms; how they are maintained; to whose advantage, or disadvantage? If asking yourself why does this definition exist, it is basically there to label and categorize a genre and large range of music which is not part of modern mainstream western commercial popular music or classical music traditions, and which originate outside the cultural sphere of western Europe and the English-speaking nations. The term world music offers a rich field of debate for popular music studies.