I was going through my old textbooks and reference books, trying to tidy my office a bit (an only slightly less hopeless endeavor than writing fiction) and found myself looking al all the notes I’d written in them. Now, I do not highlight, as that is an abomination, but I used to be in the habit of reading any sort of non-fiction with a pencil in hand. These days I tend not to do that, except when reading technical articles, because often I intend to give away the book afterward or sell it to a used bookstore: I’ve been trying to keep the number of books in the house down so that I don’t get overwhelmed, but in the process I wonder: am I getting less out of those books that I read, including the ones I keep?

So now I’m curious what habits other people have in terms of annotating books. Do you do it at all? Non-fiction/fiction? Do you write more or less than you used to?