Based on existing research on social networking and information seeking, it was proposed that Facebook.com use could be conceptualized as serving two primary goals: passive social browsing (i.e., newsfeeds) and extractive social searching (i.e., friends' profiles). This study explored whether these categories adequately reflect Facebook use and whether they moderate physiological indicators of emotion. Thirty-six participants navigated Facebook.com while their on-screen activity and physiological responses associated with motivation and emotion were recorded. Results showed that the majority of screens encountered during Facebook use could be categorized as devoted to social browsing or social searching. Participants spent more time on social browsing than they spent on social searching. Skin-conductance data indicated that sympathetic activation diminished during the course of both social browsing and social searching. Facial EMG data indicated that participants experienced more pleasantness during the course of social searching than they experienced during social browsing. These results are discussed in terms of existing social-networking research and an evaluative space model of emotion.