Presenting contacts to a social networking system user based on user interactions with additional users and with groups

A social networking system selects a set of contacts for presentation to a user of the social networking system. A contact is an additional user or a group of users maintained by the social networking system. To select the set of contacts, the social networking system generates scores associated with additional users of the social networking system and groups of users based on interactions between the user and various additional users and between the user and groups of users. Based on the scores associated with additional users and with groups of users, the social networking system selects a set of contacts from the additional users and the groups of users. Information identifying the set of contacts is communicated from the social networking system to a client device for presentation to the user.