Though web is the major modern advertising outlet, print is still important for a number of reasons. People still like to hold something in their hands, but also print is a portion of a lot of projects - product packaging, DVD covers, movie posters, etc. There are many aspects that go into a successful print design - attractive graphics, typography design, layout, color contrast ratio, focal point, message, quality of the imagery, and more. If done right, it creates a powerful impact.
One great example is a book cover. They say you can't judge a book by its cover, but it's hard not to when it's all you've seen of the book. Postcards and other direct mail are popular, especially during the holiday season. Handing out company brochures to first-time customers is a great opportunity to make a good impression. Posters are another irreplacable use for print.