2001: A Space Odyssey?

We just watched 2001: A Space Odyssey. I had never seen it before. Always kind of wanted to. It is a really famous film, and it got 4 stars, so it was sure to be good. But I have no idea what it was about!! I have never been so confused. Does anyone know?? I would really like some answers.

I even looked online to find some sort of explanation to it all, but the only thing I am sure of now is that Stanley Kubrick was a fruit.