Web search leader Google Inc is testing an Internet site for sharing knowledge about any subject under the sun, one that could eventually compete with the popular user-edited encyclopedia Wikipedia. Google's "knol" project started earlier this week and is working with a group of writers by invitation only, Google vice president of engineering Udi Manber wrote in a company blog post.

"There are millions of people who possess useful knowledge that they would love to share, and there are billions of people who can benefit from it," Manber said in the post.

"The goal is for knols to cover all topics, from scientific concepts, to medical information ... to how-to-fix-it instructions."

The word "knol" is used to refer to the project and to an entry on the shared Web site. Google's site will identify the authors posting the information. It will not serve as an editor of the information or endorse what is written on the site.

The site will eventually be opened to the general public and allow users to submit comments, questions or edits, as well as rate posts. Knol writers will be able to include ads in their posts, sharing the revenue with Google.