An engaging guide to the most important free speech rules, rationales, and debates, including the strongest arguments for and against protecting the most controversial speech, such as hate speech and disinformation. This concise but comprehensive book engagingly lays out specific answers to myriad topical questions about free speech law, and also general explanations of how and why the law distinguishes between protected and punishable speech. Free Speech provides the essential background for understanding and contributing to our burgeoning debates about whether to protect speech with various kinds of controversial content, such as hate speech and disinformation: the applicable legal tenets and the strongest arguments for and against them. The book focuses on modern First Amendment law, explaining the historic factors that propelled its evolution in a more speech-protective direction - in particular, the Civil Rights Movement. It highlights the many cases, involving multiple issues, in which robust speech-protective principles aided advocates of racial justice and other human rights causes. The book also shows how these holdings reflect universal, timeless values, which have been incorporated in many other legal systems, and have inspired countless thinkers and activists alike. Without oversimplifying the complexities of free speech law, the book's lively question-and-answer format summarizes this law in an understandable, interesting, and memorable fashion. It addresses the issues in a logical sequence, presenting colorful facts and eloquent language from landmark Supreme Court opinions. It will be illuminating to a wide range of readers, from those who know nothing about free speech law, to those who have studied it but seek a well-organized summary of major doctrinal rules, as well as insights into their background, rationales, and interconnections.