It is wide and vast.
The foundation of that would be the writers. You identify movies, but for every movie there is a writer; for every dance, there is a creator who creates the story behind it. For every book, for every novel, for every single discipline within the cultural industry, there is a writer. They are in fact the foundation.
You would have a mid-sized portion directed to the writing of books, and then a small portion of every other discipline would relate to writers. The bottom line, in answer to your question, is that writers are the foundation to it.