College vs University

[LwyrFirat]

What is the difference between college and University? The usage of these 2 words is it the same both in American and British English?

[RonBee]

A college can be a part of a university, but the reverse is not true.

~R

[LwyrFirat]

Is this the only difference? For example can we do postgraduate studies in colleges? or If I had a classmate from an undergraduate course, would I say; we were friends from the college or university.?

[Great]

I think that university is a name for many colleges that are gathering in one area

[RonBee]

Is this the only difference? For example can we do postgraduate studies in colleges?

In a word, yes.

Or If I had a classmate from an undergraduate course, would I say; we were friends from the college or university.?

You could use either one.

~R