Google Inc will begin allowing users to personally endorse search results and Web pages, its latest attempt to stave off rival Facebook Inc while trying to jump onboard a social networking boom.

The so-called "+1" button will start to appear alongside Google search results for select users from Wednesday, letting people recommend specific search results to friends and contacts by clicking on that button.

Eventually, the feature may begin to influence the ranking of search results, though that is only under consideration. Results are now ranked via a closely guarded algorithm.

The world's leader in Internet search is battling to maintain its share of Web surfers' time and attention, which is increasingly getting taken up by Facebook, Twitter and other social networks. But it has struggled to find its footing in the nascent market.

Its last attempt to create a social network — Buzz — has not fared well. A flood of complaints about how Buzz handled user privacy cast a pall over the product. On Wednesday, Google announced it had reached a settlement with regulators under which it agreed to independent privacy audits every two years.

With the new +1 buttons, Google aims to counter one of Facebook's most popular features. The new feature comes nearly a year after Facebook began offering special "Like" buttons to websites, creating a personalized recommendation system that some analysts believe could challenge the traditional ranking algorithms that search engines use to find online information.

Google said that +1 recommendations will also appear in the paid ads that Google displays alongside its search results. In its internal tests, Google found that including the recommendations boosted the rates at which people click on the ads, executives told Reuters in an interview on Tuesday.

Eventually, Google plans to let third-party websites feature +1 buttons directly on their own pages, the company said.