What is the difference between race and ethnicity?
Dalton Conley
While race and ethnicity share an ideology of common ancestry, they differ in several ways. First of all, race is primarily unitary.
You can only have one race, while you can claim multiple ethnic affiliations. You can identify ethnically as Irish and Polish, but you have to be essentially either black or white. The fundamental difference is that race is socially imposed and hierarchical. There is an inequality built into the system. Furthermore, you have no control over your race; it's how you're perceived by others. For example, I have a friend who was born in Korea to Korean parents, but as an infant, she was adopted by an Italian family in Italy. Ethnically, she feels Italian: she eats Italian food, she speaks Italian, she knows Italian history and culture. She knows nothing about Korean history and culture. But when she comes to the United States, she's treated racially as Asian.
http://www.pbs.org/race/000_About/002_04-experts-03-02.htm