Bing is adding some new social features to its search engine, by letting users comment and "like" their Facebook friends' posts directly on the site.
The new tools constitute yet another expansion to the Microsoft search site to make it more interactive and useful as the company seeks to distinguish itself from Google search.
In March Bing expanded its centre column to incorporate more social information from Facebook, Twitter and Klout into how it displays search results involving people. In January its right-hand Social Sidebar was scaled out to include more content from users' Facebook friends such as status updates, shared links and comments.
Previously, users could see that content, but could not interact with it without leaving the Bing site. But with the latest expansion, they can.
"Now you can see what your friends might know about what you're searching for and engage with them directly without leaving the search page," Bing said Friday in a blog post.
As an example, if a person is searching for tickets to a Beyonce concert, and a friend posted on Facebook that she has an extra ticket, the person could comment directly on the post on the Bing site to let the friend know that he would like to join her for the concert, Bing said.
The person has to be signed into Facebook for the feature to work. The tool honors the user's account settings and won't share any information without the person's approval, Bing said.
There does not appear to be any restriction on how old the Facebook posts can be.
The feature's focus is on surfacing the most relevant information for the searcher, but on average the technology looks at roughly two years' worth of Facebook data for each person, a Microsoft spokesperson said.
For instance, searching for the just-released film "The Great Gatsby" displayed Facebook posts from as far back as 2011, some of which did not even refer to the recent Hollywood adaptation of the book.
The flow of information between Bing and Facebook goes both ways. In January Facebook announced the beta launch of Graph Search, a social search tool designed to let users discover a wider range of information across the social network. When there are holes in the Graph Search results, information from Bing will be weaved in, Facebook said.
Bing originally rolled out its right-hand Social Sidebar last year, and since then "we've been exploring ways to make it more useful," the site said Friday.
Google is by far the largest player in search, with Yahoo and Bing occupying smaller pieces of the overall market. While it is not strictly social, since last year Google has been developing its Knowledge Graph, which is designed to make the site smarter in understanding ambiguities in language and the context within search.