NEW YORK---Booksellers and technology companies are diving into the world of digital books. Sony Corp is selling the Reader Digital Book for $299, while giant online shopping company Amazon.com offers the Kindle for $399. The digital books are light, easy on the eyes and let readers carry around as many as 200 titles in hardware that weighs less than a pound. But to some people, there's something missing. "It's , I guess, the feel of holding a book that someone really put a lot of effort into writing," said Katy Farina, 21. Farina, a college student who was browsing   at a bookstore, said, "It feels real, while the reader separates you a little bit from the story." Harry Howe, a professor, said he might use an e-book reader in search of materials while away from home, but not for reading a novel. "It's just not a physical experience that I'm yet comfortable with. On the other hand, I didn't grow up reading things on websites." Farina said she would like a reader for travelling because she would not have to transport so many books. "To put 10 books on your Sony reader or on your Kindle is a lot better than carrying 10 books," she said. Neither Sony nor Amazon would say how many machines they have sold, but enough people are interested in trying them out. An Amazon official at the Consumer Electronics Show in Las Vegas this week said the Kindle sold out on its first day in 6 hours. And for people hesitating between paper and e-books, Sony does offer a compromising -- an optional paper cover. "I think it's a clever move." Said Howe. What's the main idea of the passage?
E-books are better than paper books. E-books are becoming more and more popular. E-books read well, but some people prefer paper books. E-books will take the place of paper books one day.