[xhedley]

For technical books that I am reading for understanding I prefer paper books. My memory filing system for things I have read sometimes uses tactile, visual and physical clues which exist for paper books but not for ebooks. The vague memory of a concept from a book may come back to me with a sense of the size, shape, colour of the book, which page the passage was on, whether it was 25% or 50% through the book and so on. These physical memories help put me back in the "moment of comprehension when I was reading" so I can recall the details.

Evidence that paper is better for reading comprehension http://sciencenordic.com/paper-beats-computer-screens "... when you read a text on paper your understanding is deeper and longer lasting than if you read that same text on a computer [...] if you read the text on a screen you can probably recount what you read. But you cannot as readily make use of the content in other contexts. You haven’t comprehended it as deeply and assimilated it as substantially."