1. A computer implemented method comprising: storing a plurality of social network groups and user interactions performed by users of a social networking system with the plurality of social network groups; associating a set of social network groups of the plurality of social network groups with a category; selecting a set of users associated with the set of social network groups, comprising, for each social network group from the set of social network groups: identifying users performing user interactions with the social network group; for each identified user, determining a measure of user interactions of the user with the social network group; and including the user in the set of users, responsive to the measure of user interactions of the user with the social network group exceeding a threshold; selecting a set of candidate social network groups associated with the set of users, based on user interactions of users from the set of users with the candidate social network groups; receiving, by a computer, keywords associated with the category; searching for keyword occurrences in content associated with each candidate social network group provided by the users of the social networking system; determining whether each candidate social network group is associated with the category based on the keyword occurrences; storing information describing the category associated with the one or more of the candidate social network groups; and providing information describing a particular social network group to a user for performing an action, the information provided based on the category.