Stereotyping involves making assumptions or generalizations about people based on their membership in a social group. Stereotypes often evolve from a lack of exposure to other groups and a desire to categorize the world simply. They can lead to prejudice attitudes that create "us vs them" divisions between social groups. While stereotypes may involve unconscious associations, they can negatively impact how people are treated and behave. It is important to avoid making assumptions and respect individual differences instead of relying on stereotypes.