Final answer:
A group requires its members to interact with each other, while a social category consists of individuals who share a characteristic but do not need to interact. Groups include primary groups like family and secondary groups such as colleagues, whereas a social category would encompass 'Millennials' based on the time period of birth.
Step-by-step explanation:
One difference between a group and a social category is that the members of a group must interact with one another while those in a social category need not. A group consists of individuals who often have regular interactions and a sense of solidarity. Examples of groups include families as primary groups, and colleagues or classmates as secondary groups. These structures can range from a dyad (a group of two individuals) to much larger assemblies, all characterized by direct interactions among their members.
In contrast, a social category is a collection of individuals who share a certain characteristic or trait but do not necessarily interact with each other. An example would be the social category 'Millennials,' defined by the shared trait of being born between 1980 and 2000. Millennials as a whole do not have regular interaction which is necessary for a group. Thus, while they share a collective identity, they do not form a cohesive group since the interaction is not a requirement.