This guide covers United States copyright from subject matter through enforcement. It begins with what qualifies — originality, fixation, and the categories of authorship — and with the extensive list of what does not, including ideas, facts, systems, names, and useful articles. Ownership chapters cover the authorship default, the narrow work made for hire doctrine and its nine enumerated categories, joint works and the accounting duty among co-owners, and the writing requirement for transfers. Registration chapters explain why registration converts a right into a remedy, how the timing rules in section 412 govern statutory damages and fees, and how group registration works. The fair use chapter treats the four factors as courts apply them, including the recent narrowing of transformative use. Later chapters cover licensing and drafting, the DMCA notice and takedown system and its safe harbors, termination of transfers, infringement litigation and remedies, anti-circumvention, and the special problems of software, music, photography, architecture, and machine-generated material.