Is there difference between racism and classism?

I think that racism and classism have two different meanings but they both have things in common. Racism is when you dislike some one because of their race. When classism is disliking or belittling some one because they are either rich or poor. In a way I feel that yes, they are different, but they are similar. For example, when a person does not like a person who doesn't make a lot of money, they tend to use race with the reason as too. The same goes if a person were to hate a person that did make a lot of money they would tend to use race as a reason as well.