Google Inc. is hoping other websites will like its recently introduced system for recommending online content and ads.
The Internet search leader has been using a "+1" recommendation button on its own site for two months. It became available to other publishers Wednesday.
The +1 feature is similar to the Facebook "Like" button that has become a staple at thousands of websites.
Pressing the +1 or Like button enables people to recommend an article, photo, product, video, song or some other kind of material to their online connections.
The personal endorsement also says something about an individual's interests and preferences. That's something both Google and Facebook want to know more about so they can do a better job placing the online ads that generate most of their revenue.
Facebook is gaining valuable insights as people increasingly spend more of their time on its website sharing their thoughts, photos and links. It's a troubling trend for Google because much of the information posted by Facebook's more than 500 million users can't be indexed by Google's search engine.
The growing popularity of Facebook haunts Google's former CEO Eric Schmidt. In a late Tuesday appearance at the D: All Things Digital conference, Schmidt described his inability to counter the threat posed by Facebook four years ago as the biggest regret of his decade-long stint as Google's CEO. He now serves as Google's executive chairman and an adviser to company co-founder Larry Page, who replaced Schmidt as CEO nearly two months ago.
Page has made the development of more social networking features one of Google's top priorities.
Google is hoping people will latch on to the +1 button as a way of highlighting their recommendations in Google's influential search engine. The endorsements would only show up in the results of people who have told Google they share a common bond.
Personal recommendations also can be seen in the results of Microsoft Corp.'s Bing search engine. Bing is picking up the information for Facebook's Like button as part of a partnership. Microsoft has grown closer to Facebook since it paid $240 million for a 1.6 percent stake in the social networking service in 2007.
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