Explanation/Reference:
Explanation:
Yammer is Microsoft's private collaboration platform for enterprise social networking.
Unlike public social media platforms such as Twitter, Yammer only allows members to connect with other members who belong to the same email domain. This unique feature provides corporate employees with the ability to communicate privately, using a graphical user interface (GUI) that resembles Facebook.
References: https://technet.microsoft.com/en-us/library/message-and-conversation-features-in- yammer.aspx