The "+1" button represents Google Inc.'s latest imitation of Facebook in an attempt to make it easier for its users to share their insights with their online contacts.
Google hopes to benefit from its version of Facebook's "Like" button by making its search results more relevant and its ads more tempting to click.
The +1 button initially will begin appearing next to search results and ads for a relatively small number of Google users, the company said. Other websites will be also allowed to to place the +1 button next to their content, the company added.
To use the new recommendation system, users must create a Google Profile page. Any +1 clicks that a person makes will be publicly visible to their network of contacts, which is based on existing contacts in Google products such as the company's Gmail email and its instant messaging service.