How did racial discrimination come about and what caused it?

Racism refers to a person's contempt, disgust and rejection of races other than himself, which is manifested in his words and actions.

In modern times, racial discrimination began in the colonial era [1] and reached its peak in the period headed by the government apartheid system [2].

After the Second World War in the 20th century, the independence movement in the third world and the racial equality movement in western countries, the political correctness related to race became more and more serious in many countries in the world, and racial differences should not be summarized by racial discrimination. In immigrant countries, racial problems cannot be simply covered up by racial discrimination.