Google Inc. is testing a new user tool that invites people to write authoritative articles on particular subjects, a move that could put the internet search giant in direct competition with the popular online encyclopedia Wikipedia.

The user-generated knowledge project, dubbed Knol, was made available this week to a small group of users in a trial, said Google's vice-president engineering, Udi Manber, in a Thursday evening post on Google's official blog.

"We believe that many do not share that knowledge today simply because it is not easy enough to do that," wrote Manber. "Our goal is to encourage people who know a particular subject to write an authoritative article about it."

Google said it would provide tools for writing, editing and provide free hosting of the content. Authors would receive credit for their work and could choose to include Google ads on their pages, with authors getting a share of the revenue generated from those ads.

Multiple articles — called knols — on the same subject would be allowed. The articles would be ranked according to a reader voting mechanism.

"Once testing is completed, participation in knols will be completely open, and we cannot expect that all of them will be of high quality," wrote Manber. "Our job in Search Quality will be to rank the knols appropriately when they appear in Google search results."

The project, with its emphasis on individual authors, appears to take aim at Wikipedia, the online encyclopedia that anyone can write, edit or contribute to.

"Books have authors' names right on the cover, news articles have bylines, scientific articles always have authors — but somehow the web evolved without a strong standard to keep authors names highlighted," wrote Manber. "We believe that knowing who wrote what will significantly help users make better use of web content."

Anonymous contributions under scrutiny

Wikipedia has been criticized in the past for allowing anonymous contributions to the site, a policy that some have argued encourages vandalism of entries and discourages experts from writing for the website.

In March 2007, the online encyclopedia suffered a blow to its reputation when it was revealed an editor who had represented himself as a university professor was in fact a 24-year-old from Kentucky with no higher-education credentials.

Knol wouldn't be the first project to try to address this perceived shortcoming.

Earlier this year, Larry Sanger, Wikipedia's former de facto editor in chief, launched a rival online encyclopedia called Citizendium, one that would be written and edited by experts in their fields.

Sanger told CBC News that while Knol would provide authorship, its voting-by-the-masses model was unlikely to attract genuine experts.

"The notion that anyone may write a 'knol,' and be compared and ranked by 'the crowd' — not by expert peers — is apt to attract relatively little notice from experts who are very careful about where they publish," he said in an e-mail Friday.

Knol is unique, though, in that it makes the content part of Google's ad-generated business, as opposed to Wikipedia and Citizendium, which are non-profit organizations.

Sanger said such a policy wouldn't go over well with the "free culture crowd" who have made Wikipedia popular.

But he said that as a business model, it might be successful.

"Other web companies have had reasonably good success making money with such web services, and Google might make a lot of money with theirs."

Knol also marks Google's latest attempt to move into areas on the web traditionally dominated by social media, where content is created, or directed, by users. This fall, the company announced plans to build a software platform for sharing applications across the web in a manner similar to social networking site Facebook.

It also announced plans to test a way to alter search results based on user-generated voting, similar to how news aggregrator websites such as Digg and Reddit rank articles.