Microsoft will likely buy social media site Yammer

Microsoft may be set to buy social media site Yammer for just over one billion dollars, sources say.

The acquisition of Yammer, which has already agreed to the purchase, would put Microsoft in the social media game against rivals Facebook and Google.

The deal is said to be worth over one billion dollars, reported Bloomberg, and might be reached as soon as Friday evening.

Yammer, a business social networking site, would be a way of allowing Microsoft into the social-networking business without having to start from scratch, said Forbes.

Its platform could be plugged into Microsoft software like Office to allow for greater collaboration within a workplace.

The social media company, launched in 2008, has about five million corporate users and allows networking within companies to keep employees in touch with one another.

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CBS News reported that Yammer raised $85 million in funding last quarter making the total raised since 2009, $142 million.

Microsoft offcials have declined to comment on the deal.

Last May, in the largest acquisition in its history, Microsoft bought Skype for $8.5 billion, reported the Wall Street Journal.

Informationweek has reported that Microsoft said it will make a major annoucement Monday in Los Angeles.

The website speculates that the software company may unveil a tablet computer to rival that of the Apple's iPad.