The purchase of an original CD or download of music from a legal and licensed site, gives you ownership of a copy of the work. You may play the CD or music in your home for your enjoyment and that of your family and friends. You may lend the copy to your friend but not for a fee. The moment you begin to play the music in a place open to the public or in a commercial environment you are going beyond the right of the owner of a copy and enjoying the right of a copyright owner. In order to avoid this infringement you need a license from COSOTA which allows the public performance of the music.