Stereotypes are characteristics ascribed to groups of people involving gender, race, national origin and other factors. These characteristics tend to be oversimplifications of the groups involved. Stereotypes are often confused with prejudices, because, like prejudices, a stereotype is based on a prior assumption. Stereotypes are often created about people of specific cultures or races.
People like to classify, list, define, categorize, organize and quantify. This allows them feel like they have a control or a handle on things. People like to have consisted to feel safe and decrease predictability. People tend to take a shortcut. So, we look at an individual and spot something that is familiar to us and categorizing them to how this characteristic corresponds to something familiar.
We all use stereotypes, all the time, without even realizing it. People can weaken the links that connects minorities to negative stereotypes but strength the ones that connect them to positive conscious beliefs. It is important not to let generalization limit you to only considering the individual in the context of the stereotype. Stereotypes are pervasive and powerful. We rarely believe ourselves to be influenced by them, making us even more susceptible to their effects.