Race

WHAT IS RACE? (as mention in wikipedia)
The term race or racial group usually refers to the categorization of humans into populations or groups on the basis of various sets of heritable characteristics.The most widely used human racial categories are based on salient traits (especially skin color, cranial or facial features and hair texture), and self-identification.

Conceptions of race, as well as specific ways of grouping races, vary by culture and over time, and are often controversial for scientific as well as social and political reasons. The controversy ultimately revolves around whether or not the concept of race is biologically warranted; the ways in which political correctness might fuel either the affirmation or the denial of race; and the degree to which perceived differences in ability and achievement, categorized on the basis of race, are a product of inherited (i.e., genetic) traits or environmental, social and cultural factors.
Some argue that although race is a valid taxonomic concept in other species, it cannot be applied to humans. Many scientists have argued that race definitions are imprecise, arbitrary, derived from custom, have many exceptions, have many gradations, and that the numbers of races delineated vary according to the culture making the racial distinctions; thus they reject the notion that any definition of race pertaining to humans can have taxonomic rigour and validity.

Today many scientists study human genotypic and phenotypic variation using concepts such as "population" and "clinal gradation". Many contend that while racial categorizations may be marked by phenotypic or genotypic traits, the idea of race itself, and actual divisions of persons into races or racial groups, are social constructs. However, the concept of race may be useful in forensic anthropology. According to forensic anthropologist George W. Gill, "race denial" not only contradicts biological evidence, but may stem from "politically motivated censorship" in the belief that "race promotes racism".