eXtension is a collaboratively built online learning platform managed by USDA that provides science-based agricultural information 24/7. It is funded through USDA, land-grant universities, and private sources. eXtension staff oversee communities of practice, which are virtual networks of experts from multiple institutions that address topics of interest. Communities of practice benefit from technical support and applications to facilitate communication and knowledge sharing. The document discusses how social media is becoming increasingly popular and important for online communication and engagement.