Difference between College and University.

In Canada, at least up in Quebec, my girlfriend said you have to go to college for 2 years (required), then advance to University if you wish (total = 4 years+).

In the US, we all know that's not the case, as only High School is mandatory.. and college / university is technically the 'same'. Except universities are well-known, there isn't a well-known college imo?

Ex:

Penn State University
Robert Morris University
University of Pittsburgh <---- Planning on attending there the upcoming year to continue my education in Computer Information Systems, actually...