Microsoft’s message board/social network for business, Yammer, now allows administrators to invite people from outside of the Yammer network into groups for discussions and other messaging. The company made the announcement in the Yammer blog last week.
Yammer is a high-powered message board Microsoft acquired in 2012 for $ 1.2 billion. It lets groups stay in regular contact while working on projects and has become a major component of Office 365. However, it operates in any environment, including stand-alone, to serve as an internal messaging platform the way Notes and cc:Mail tried to do years ago.