This document provides an overview of copyright law as it relates to libraries. It discusses how copyright law has evolved over time from early traditions to the modern system of exclusive rights granted to creators. The document outlines the key aspects of U.S. copyright law, including the types of works protected, exclusive rights, and exceptions and limitations such as fair use. It notes the complexity of interpreting copyright law and balancing the interests of creators and users. The document advises librarians to carefully analyze questions around permission, fair use, and risk when deciding how to use or provide access to copyrighted content.