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Yammer is a tool for making companies and organizations more productive through the exchange of short frequent answers to one simple question: 'What are you working on?' As employees answer that question, a feed is created in one central location enabling co-workers to discuss ideas, post news, ask questions, and share links and other information. Yammer also serves as a company directory in which every employee has a profile and as a knowledge base where past conversations can be easily accessed and referenced.