Final answer:
A group requires its members to interact with one another, while a social category does not necessitate interaction. The Millennial generation is an example of a social category because they share similar characteristics but do not typically interact with each other.
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 is characterized by individuals who come together for a common purpose or share a sense of identity, while a social category refers to people who share similar characteristics but are not tied to one another in any way. For example, the Millennial generation is considered a social category because they share similar birth years, but they do not interact as a whole.