Consumers of music from online sources have a number of options. Free tracks are legally available from musicians’ websites, or as samples from music stores, or tracks can be made available illegally by users who do not hold the copyright, through file-sharing or music blogs. Music files can be purchased by subscription or per track from a range of online music stores including major retailers and independent labels. Each method of acquiring music has its relative disadvantages in terms of cost, convenience, quality or legality.
International Handbook of Internet Research p. 295-308