"We've always followed our own path, rather than conform to the conventional practices of the publishing industry," said founder and CEO Tim O'Reilly. "Safari is a logical extension of that approach. In designing the service, we've exploded the notion of 'book' and built a front end for the content of our books that truly harnesses the power of the Web."

Safari transforms a collection of O'Reilly books into a meta-book that's more than the sum of its parts. A subscription-based service, it allows you to build a customized online library. You pay a flat monthly fee, based on the number of titles to which you subscribe. And you can change the titles in your subscription as your needs change. So if you've outgrown Learning Perl, you can trade it in for Advanced Perl Programming. Safari will include 50 of O'Reilly's best-selling books at launch, and the company will add titles until the entire O'Reilly publishing list is available.