White supremacy or white supremacism is a racist ideology based upon the belief that white people are superior in many ways to people of other races and that therefore white people should be dominant over other races. White supremacy has roots in scientific racism and often relies on pseudoscientific arguments. Like most similar movements such as neo-Nazism, white supremacists typically oppose people of color and people of most religions.
The term is also typically used to describe a political ideology that perpetuates and maintains the social, political, historical or industrial domination by white people (as evidenced by historical and contemporary sociopolitical structures such as the Atlantic slave trade, Jim Crow laws in the United States, and apartheid in South Africa). Different forms of white supremacism put forth different conceptions of who is considered white, and different white supremacists identify various racial and cultural groups as their primary enemy.
In academic usage, particularly in usage drawing on critical race theory, the term "white supremacy" can also refer to a political or socio-economic system where white people enjoy a structural advantage (privilege) over other ethnic groups, both at a collective and an individual level. Wikipedia