OSA is a civic association who is an important bridge between the authors and the users of their works. The authors provide services related to the selection and subsequent billing of royalties, including the processing of data from users and the use of legal services. Users can easily access the legal use of music from all genres around the world. OSA has two members of membership, affilated members and full members, both who need to have at least one publicly available work.
Music Publishing is the business of protecting and promoting song copyrights and collecting the royalties that these copyrights generate. Think of a song as intellectual property (it's an original piece of art!), and music publishing as the business that makes sure that songwriters get paid a fair compensation when their intellectual property is used by companies. Those companies could be record labels (mechanical royalties), radio stations, bars, and restaurants (performance royalties), or film studios and advertising agencies (sync license fees), and many more.