SOCIAL DEAL: Microsoft has agreed to buy Internet startup Yammer for $1.2 billion in an effort to provide more Facebook-like features to its corporate customers. Yammer Inc. specializes in building private social networks that enable employees within the company to track each other’s work.

THE MOTIVE: The Yammer deal announced Monday is part of Microsoft Corp.’s effort to adapt to changing technology that is driving demand for more Internet-connected services and social networking tools.