Final answer:
A generalization that is not based on reality and is simplistically applied to individuals or groups is known as a stereotype, which can lead to prejudices and is not supported by individual differences.
Step-by-step explanation:
A generalization made about an individual or group that is not based on reality is called a stereotype. Stereotypes are oversimplified and often negative generalizations that do not take individual differences into account. They can be based on various characteristics such as race, ethnicity, gender, or age.
Hasty generalization is a related concept that refers to conclusions made hastily without sufficient evidence. However, the term 'stereotype' more accurately describes a generalization that is not just hastily made but also inaccurately reflects reality.
Stereotyping can be a form of prejudice when these generalizations become overgeneralized and applied to all members of a group. It is important to distinguish between valid generalizations based on evidence and stereotypes that are unfounded and potentially harmful biases.