Why do so many Americans hate Trump? I just don't get it.

I'm not trying to be political, I just don't get why so many people hate him. It feels like you never see anyone say "I'm so glad he's President". How can there be so much hate for one person? He's a billionaire who is the president of the United States. I don't see how he's hurting people. Can someone give me a real reason why they hate him? I'm not trying to be an ass, I just don't get it.