The terms Discrimination and Reverse discrimination are used to describe policies or habits of social discrimination with an implication of unfairness.
Social discrimination on certain grounds is now illegal in many countries, but in some affirmative action favoring the minorities is required by law (e.g. USA), while in others such action would be regarded as reverse discrimination, and would be illegal (e.g. UK.)
Opposing views of Affirmative Action are discussed more fully in that article.
See also: Affirmative action, Racial quota, Discrimination, Racism, Anti-racism, Sexism, Grutter v. Bollinger, Bakke case