What is censorship? Discuss the pros and or cons of censoring material, especially for people under the age of 18. When is it appropriate?

Censorship is blocking certain things, like TV shows, or music, because it is innappropriate for people under a certain age. The pros for censorship are that some material may be too much for some people to handle. Many books or movies have things that 13 year olds shouldn't be learning about, so censorship would partially stop those kids from reading about them. The cons, however, are that many people can handle it, and for a book to be censoreds defeats the purpose of reading to become more knowledgable.
I personally don't like the idea of censorship, for people any age. People write things because they want them to be read, and interpreted. If they get censored, the writer as a whole gets knocked down, because people can't read their books. I don't think censorship should ever be appropriate, and if anyone tried to censor a book that I wrote, or even that I just really loved, I would fight for it, because I believe that books are written for a reason, and they shouldn't be taken away.