Final answer:
Discrimination refers to biased actions against an individual or group, distinct from stereotypes, which are oversimplified ideas, and prejudice, which involves negative thoughts and feelings. Discrimination is evidenced in both overt policies and subtler forms such as social exclusion.
Step-by-step explanation:
When we talk about the question '(like themselves and exclude others who are unlike them)', it is addressing the concept of discrimination. Discrimination refers to biased actions against an individual or group, typically based on inherent characteristics such as race, ethnicity, age, religion, or sexual orientation. Unlike a stereotype, which is an oversimplified idea about a group, or prejudice, which involves negative thoughts and feelings, discrimination consists of actions. These actions can manifest in various forms, from overt policies like Jim Crow laws to subtler forms such as biased hiring practices or social exclusion. Discrimination has been a persistent issue throughout history and remains a topic of great importance in understanding social dynamics and civil rights.