How I Came to Appreciate Fan Fiction

I've been reading genre fiction (romance, mystery, SFF) for a very long time, but I didn't become aware of fan fiction as a category of writing, much less its role in creating community, until I found internet blogs about fiction writing. Back when I was reading mystery blogs regularly, I ran across a ranting post on the illegitimacy of writing stories using other authors' characters and worlds. Many commenters in the very long thread attempted to explain what attracted them, and to a person ...