Scientific racism

Scientific racism is the use of science to support racism. In the 19th century, scientists divided humankind into different groups called "races".
For instance, the group of black people was called "Black race" or "Negroid race". Many scientists said that white people were superior to (better than) black people. In this way, scientists supported slavery and Jim Crow laws.
In the 19th century, some scientists said that Jews were a race. People like Houston Steward Chamberlain wrote that Jews were a danger to other people. Adolf Hitler read some of their books. He ordered the Holocaust in which about 6 million Jews were murdered.
Today, scientists agree that there is only one human race. Modern genetic research has shown that the idea of different races was wrong. Scientists also say that the "belief in races" is a bad thing that has caused much damage.