Google, in a challenge to Wikipedia, has created a user-generated online encyclopedia called Knol that identifies its writers instead of keeping them anonymous.
"Earlier this week, we started inviting a selected group of people to try a new, free tool that we are calling Knol, which stands for a unit of knowledge," the company wrote on its blog. "Our goal is to encourage people who know a particular subject to write an authoritative article about it."
Although it's already drawing comparisons to the best-known user-generated Web encyclopedia Wikipedia, Knol is different in a few key ways. First, unlike Wikipedia, authors of articles on Google's site are highlighted, not hidden. Similarly, articles on Knol aren't collaborative; they are written by just a single author.
"The key idea behind the Knol project is to highlight authors," Google wrote. "We believe that knowing who wrote what will significantly help users make better use of Web content."
Users of the site, which is in beta-testing and invitation only, can still participate by ranking the usefulness of entries, adding comments and asking questions. Google will not serve as an editor and expects several knols on each topic.
But can Knol unseat current online leader Wikipedia? Owned by the nonprofit Wikimedia Foundation, Wikipedia was founded in January 2001. It has more than 8.2 million articles in more than 200 languages, including more than 2 million in English.
Even without added competition from Knol and similar sites like Squidoo, Wikipedia has faced credibility challenges that can be primarily attributed to the collaborative nature of its entries. In the Wikipedia model, users write articles and other users can edit the entries by adding or deleting information.
In theory, the entries get more thorough and accurate as they live on the site. The reality, however, is not so simple.
In August 2007, a British graduate student developed WikiScanner, a program that identified the authors behind Wikipedia edits. The program revealed that people at the IP addresses of several major companies made changes to their own or competitors' entries.
"That's been a fairly serious problem with Wikipedia," Silicon Valley technology analyst Rob Enderle said. "Way too many personal attacks."
Enderle contends that identifying the author gives Knol an extra layer of credibility.
Google's main challenge in competing with Wikipedia will be people's current Web habits, according to Enderle.
"People are creatures of habit," he said. "If Wikipedia can deal with a trust problem, they can stand up against this."
However Wikipedia fares, there is room for more than one user-generated encyclopedia, Silicon Valley technology forecaster Paul Saffo told ABCNEWS.com.
"On my desk next to my computer I have a reference shelf -- dictionaries, thesauruses," Saffo said. "This same thing will be true on the Web. There's plenty of space. I think the two will reinforce each other."
Knol's respect for authorship will be a huge boon for Google and differentiate it from competitors like Wikipedia and Squidoo, Saffo said.
"How many people are going to labor hours and hours for Wikipedia [when it's anonymous]? In this case you're the author and it's your reputation," Saffo said. "I can see this being used for graduate students out of school trying to build a reputation, professors thinking about getting tenure. It's a star-making machine for the right kind of intellectuals."
Knol will even work for people who aren't experts, Saffo said.
"Reputation is a really powerful incentive for people to contribute," he said. "This plays perfectly to the whole notion to the rise of amateurs."
In addition to it's "star-making" potential, Knol has an added incentive -- it allows its authors to make money from their writing, Saffo said.
"At the discretion of the author, a knol may include ads," Google posted on its blog. "If an author chooses to include ads, Google will provide the author with substantial revenue share from the proceeds of those ads."
It's ways too soon to tell what effect that Knol will have on Wikipedia and other sites like it, but when the world's largest search engine and its scoring ability gets behind something, people take notice.
"Wikipedia allows group contribution, but it doesn't allow ranking. ... Google is applying ranking to that. Which method is a better way to show reliability?" Saffo said. "[They're] two very different approaches and each has it advantage."