What Makes a Book? In essence, the two formats are very similar. Both allow you to do the most important thing - read a book. The text is the important thing, not the medium. Reading Sumerian legends on clay tablets can feel more "authentic", but doesn't necessarily enhance your understanding of the subject matter - just your experience. Depending on the type of material you'd like to read / look at, however, one does have advantages over the other.
The "Classic" Paper Book. Paper books offer multiple advantages: They're easily obtainable (Bookstores are everywhere). They're easily portable. They don't normally cause significant eye-strain. They're cheap. Okay, that much was obvious. Specifically, some types of content paper books are better for are: Textbooks (or any books which are generally large-format). Picture / Photo books. Another factor to bear in mind is that paper books don't need power to function. They can be read anywhere with sufficient light, and are perfect travelling companions for exactly this reason. The obvious cons are: Paper books are bulky and heavy. Carrying more than 2-3 around can become a chore. You need a light source to read them - another thing that you'll probably carry around. If you make notes in them, those notes are there to stay (Yes, even pencil. You can always see the imprints, even if you erase every last shred of graphite).
The eBook eBooks offer the following obvious advantages (assuming you have an ebook reader): They're easily readable. Most readers offer zoom functions, letter resizing, and so forth. They're easily portable. You can carry multiple books on one device. They're much more environmentally friendly. You don't have to kill a few trees for each book, and let's not even talk about the ink. Recycling only goes so far. Note-taking is much more powerful, and the notes you write can be found and referenced quickly and easily. And they don't have to be permanent. Lighting conditions essentially become meaningless. Many readers incorporate display lighting allowing you to read whenever and whereever you like.