1. A method comprising: determining, by one or more processors, one or more topics associated with a message based at least in part on message data included in the message; determining, by the one or more processors, knowledge data describing the one or more topics associated with the message; determining, by the one or more processors, social activity data describing one or more user activities associated with a group of one or more social users based at least in part on the knowledge data, the one or more user activities describing the one or more topics; generating, by the one or more processors, a selectable tag based at least in part on the social activity data describing the one or more user activities, a selection of the selectable tag causing a display of the social activity data associated with the message; and generating, by the one or more processors, graphical user interface data for displaying the social activity data associated with the message in response to the selectable tag being selected.