There are many types of discrimination in our society. Let me list a few of them.
First, for all our progress, there is still racial discrimination. By and large society is still separated by race. We see this on college campuses, the work place, and neighborhoods. We also see this very clearly in hate crimes, which occur on a daily basis. Just think about the LA riots a few decades ago. Also it is reported that hate threats are up 400% with President Obama, the highest on record.
Second, there is also gender discrimination. For example, men tend to make more than women in the work place, even when they do the same work. Recently, there is even a class action suit against Walmart. Women state that they are being overlooked for managerial positions.
Third, there is discrimination when it comes to social class. People treat those who have money better than those without. Also in many ways the government ironically provides additional benefits for the wealthiest people. For example, Warren Buffet pays a lower tax percentage than a secretary.