Is there a difference between racism and classism?

According to the Merriam-Webster Dictionary, racism is "a belief that race is the primary determinant of human traits and capacities and that racial differences produce an inherent superiority of a particular race"

In simple words, it is a hatred of one person by another just because of skin color, language or customs. Throughout the history it has influenced slavery, wars, and politics of many countries.

Classism is at the same time different and the same. Dictionaries define it as "prejudice or discrimination based on class", which distinguishes the two, but if we go back to Steele's essay "On Being Black and Middle Class" we come to see that black people in the USA are often victims of classism, which draws a conclusion that racism and classism could be considered a same thing.

However, I think that we could apply this conclusion only to the United States, where rasism has been a major issue since the colonial era. In the countries where race diversity is not that common, classism play a completely separate role from racial discrimination.