Following eight months of testing, Google this week has officially revealed its rival to Wikipedia, known as Knol. Knol had been limited to an invitation-only audience of contributors and readers for the past seven months. The new site features articles about a range of specific topics written by self-proclaimed experts in the field.

According to Google, individuals will author articles but the revision process will be collaborative. Any reader may suggest changes to any Knol, and edits will pass through a moderation process that Google calls moderated collaboration before the edits will be applied to the Knol in question. Readers can also rate, write reviews of, and submit comments to Knols.

Google will also provide Knol authors the option to include AdSense ads alongside their Knols. The contributing author and Google will share any revenue generated from the ads. In another aspect, Google has signed a deal with the New Yorker magazine, allowing authors to add one cartoon per entry from the publication's cartoon repository.