Racism is the belief in the superiority of one race over another, which often results in discrimination and prejudice towards people based on their race or ethnicity. Today, the use of the term "racism" does not easily fall under a single definition.^[1]
The ideology underlying racist practices often includes the idea that humans can be subdivided into distinct groups that are different due to their social behavior and their innate capacities as well as the idea that they can be ranked as inferior or superior.^[2] The Holocaust is a classic example of institutionalized racism which led to the death of millions of people based on race. While the concepts of race and ethnicity are considered to be separate in contemporary social science, the two terms have a long history of equivalence in both popular usage and older social science literature. "Ethnicity" is often used in a sense close to one traditionally attributed to "race": the division of human groups based on qualities assumed to be essential or innate to the group (e.g. shared ancestry or shared behavior).