In Fahrenheit 451, owning and reading books is illegal. Members of society focus only on entertainment, immediate gratification and speeding through life. If books are found, they are burned and their owner is arrested. If the owner refuses to abandon the books, as is the case with the Old Woman, he or she often dies, burning along with them. People with interests outside of technology and entertainment are viewed as strange, and possible threats.
In the book, Bradbury doesn't give a clear explanation of why censorship has become so great in this futuristic society. Rather, the author alludes to a variety of causes. Fast cars, loud music, and massive advertisements create an over stimulated society without room for literature, self-reflection, or appreciation of nature. Bradbury gives the reader a brief description of how society slowly lost interest in books, first condensing them, then relying simply on titles, and finally forgetting about them all together.
Bradbury also alludes to the idea that different "minority" groups were offended by certain types of literature. In his discussion with Montag, Beatty mentions dog lovers offended by books about cats, and cat lovers offended by books about dogs. The reader can only assume which minority groups Bradbury was truly referring to. Finally, in the Afterword to Fahrenheit 451, Bradbury clearly expresses his own sensitivity to attempts to restrict his writing. For example, he feels censored by letters suggesting he should give stronger roles to women or black men. Bradbury sees such suggestions and interventions as the first step towards censorship and book burning.
