Blanket licenses are a type of license allowing one to use all the compositions covered under the agreement with no limit on use for one payment (usually annual). most commonly refer to licenses issued by performing rights organizations (PRO) to licensees (restaurants, bars, clubs, etc.) who wish to use the entire catalog of a PRO.

Making Your Own Music: Songwriting Basics
Songwriting is an excellent way to express your thoughts and feelings and to communicate them to your friends and family, even if you have no aspirations of musical fame or fortune.