Directly from my university’s intro-level sociology textbook. Clearly not rocket science.

“Racism is a belief in the superiority of one or more racial groups that creates and maintains a racial hierarchy. While people of all races can hold stereotypes and prejudice about members of other racial groups, only members of dominant racial groups can be racist. Racism requires prejudice and power. The very idea of race was an invention of white people designed to lend support to the notion that whites are inherently superior to and should be granted more power and privilege than people of color.”

Also for context: university in the United States.