How racism or ethnocentrism works to produce an "us vs. them" worldview. Ethnocentrism is defined by our textbook as "the attitude that other societies' customs and ideas can be judged in the context of one's own culture

Racism is the notion that humanity can be categorized into different races, each of which is assigned a set of characteristics and ranked by value. Racism is and has been the basis of discrimination or segregation.

Until the end of the 20th century, racism was usually based on assumed biological and hereditary differences between peoples. In recent decades, it has been common to extend the concept of racism to the degradation of other ethnic, cultural or religious groups, without necessarily justifying biological differences such as appearance. A common feature of both understandings of racism is that people's identities are judged on the basis of prejudices related to the person's group affiliation.