You can take a book to the beach without worrying about sand getting in its works. You can take it to bed without being nervous about it falling to the floor should you nod off. You can spill coffee on it. You can sit on it. You can put it down on a table, open to the page you're reading, and when you pick it up a few days later it will still be exactly as you left it. You never have to be concerned about plugging a book into an outlet or having its battery die.