Today’s question comes from Conspiracy-Girl: "I’m still relatively new to this meme so I’m not sure if this has been asked yet, but I’m curious how many of us write notes in our books. Are you a Footprint Leaver or a Preservationist?"
In fiction books, I'm generally a Preservationist (though that does not extend to turning down the corners of pages to mark my place; I know, it's slovenly). The only time I'll mark up a fiction book is if I find a passage I think is particularly clever or beautifully written, and then I'll underline or put a big star next to it.
In non-fiction books, I'm a Footprint Leaver. I make notes to myself, questions, responses to theories, etc. They feel more like textbooks to me, and I wrote all over those.
Edited to add: I have to make a distinction here: I never, EVER, write in library books, or of course books I've borrowed. Footnoting is strictly for books I own.