Racism or racialism is a form of race, especially the belief that one raceis superior to another. Racism may be expressed individually and consciously, through explicit thoughts, feelings, or acts, or socially and unconsciously, through institutions that promote inequality between races.
In the 19thcentury many legitimized racist beliefs and practices through scientifictheories about biological differences among races. Today, most scientists haverejected the biological basis of race or the validity of "race" as a scientificconcept. Racism, then, becomes discrimination based on alleged race. Raciststhemselves usually do believe that humans are divided into different races.
There are two main definitions of racism today. One of them states thatracism is dicrimination based on alleged race, the other - newer - one statesthat racism has started to include also discrimination based on religion orculture