University vs College The difference between a college and a university is that generally a college offers set of degrees in one specific area whereas a university has a collection of colleges. For instance when someone goes to a university he/she will graduate from one of their colleges such as Business College or Engineering College. Most of the time, universities are well known and they are larger than colleges. The difference between both college and university varies between the USA and the rest of the world. for more detail: http://www.differencebetween.net/miscellaneous/difference-between-colleges-and-universities/

In the UK college is 17-18 and university is 18+. In the US I think college is an 18+. What they call college we call university.

There's no good single explanation for this. It depends on which region you are in. Tom's answer explains it pretty well. In my case, my secondary schooling was called "college", then I went to university. However, if someone told me "they go to college", I'd assume they were studying for a degree in the US.