Racism is a symptom of the human need to discriminate. We begin by discriminating sounds so that we can attain language. We learn to discriminate between colour, taste, touch, etc. This ability to discrimate serves many purposes.
Racism is a perversion of our innate ability to discriminate. This perversion has been fuelled by socio-economic-political forces to keep groups of people separated so that they do not become a united force. Racism serves no purpose except to divide.