Answer:
All books were banned. The only thing allowed was comics books.
and scripts for the people in the parlor. books were banned because they can be viewed in different ways and cause people to think. the government didnt want this.
you may say "but isn't a script like a book?"
the answer is no because reading a script is just basically being told to do something.
you are being controlled, which is what the government wants in Fahrenheit 451. the government wants to control the people completely and doesnt want anybody to think any differently than anyone else. thus people don't even have imaginations. theyre robatized.