Cognitive social structures (CSS) is the focus of research that investigates how individuals perceive their own social structure (e.g. members of an organization, friend group, hierarchy, company employees, etc.). It is part of social network research and uses social network analysis to understand how various factors affect one's cognitive representation of the network (i.e. the individual's belief of who is connected to whom). Importantly, an individual's perception of the network may be different than reality. In fact, these differences between the perceived network and the actual network are the focus of many studies that seek insight into how we think about others and our relationships.