How does the First Amendment of the U.S. Constitution protect citizens from government censorship?

The First Amendment of the U.S. Constitution protects citizens from government censorship by guaranteeing freedom of speech and of the press. This means the government generally cannot make laws that restrict the content of expression. This protection extends beyond political speech to cover science, religion, art, and personal opinions.1234

However, this freedom is not absolute. There are exceptions, such as speech that incites imminent lawless action, defamation, fraud, obscenity, and threats. The government can also regulate the time, place, and manner of speech if the restrictions are content-neutral and leave open alternative ways for expression. Prior restraint, or preventing publication before it occurs, is particularly difficult for the government to implement.156