[T]he Wikibooks project...[is the] attempt [by Jimmy Wales and the Wikimedia Foundation] to create a comprehensive, kindergarten-to-college curriculum of textbooks that are free and freely distributable, based on an open-source development model. Created in the same mold as the Wikipedia project --the open-source encyclopedia that lets anyone create or edit an article and that now has nearly 747,000 entries in English alone-- Wikibooks is still in its earliest stages. Yet because of Wikibooks' digital model, in which material written for the project can be as short or as long as needed, and be easily manipulated, read and edited, Wales and others believe it can pose a major challenge to the publishing industry's hold on the world of textbooks. "The purpose is really contained in the word 'freely licensed,' which is to make available to anyone in the world, in any language, a curriculum that they can copy, redistribute and modify, for whatever purpose they may have, for free," Wales said. The publishing industry is "going to have to recognize that there's a fundamental shift in the marketplace," he added. "Some of them will prosper. Some of them will figure out the new regime and find out ways to add value. Others will stick their heads in the sand and get slaughtered."...Today, Wikibooks contains 11,426 submissions. The topics covered range from biology to economics in New Zealand. Because the books are digital and open source, any teacher can decide to assign one and simply point students to PDFs they can print. But Wales is the first to acknowledge that the project is several years away from maturity. "It's still a young project," he said. "I would consider it to be mission accomplished when we could point and say, 'Well, you could teach yourself, or someone could teach you using these materials, (anything) from the kindergarten to the university level.'" Naturally, Wikibooks isn't the only effort to amass a vast collection of digital books. Google has been building its library and print projects since last year. But where Google's project is a digital database of often copyrighted works, Wikibooks' material is all work that has been made free to the public.