What is racism to you?

I was reading the question asking whether racism is dead, and I began to wonder what people meant by “racism.” There are many acts and thoughts that various people might consider to be racist. Some are over, some are more subtle, and some might even be projections.

What does racism mean to you? Please try to be as specific as possible, by giving examples of acts and words and thoughts. I hope this will cover the territory from overt acts to things that are very subtle. Thanks.