I've been taking a lot of mathematics courses, and I am getting to where I will eventually be doing upper division mathematics. I was looking for someone to explain some insight on how upper division math courses differ from the traditional calculus sequence. For example, number theory, abstract algebra, computational methods, graph theory, or optimization. Will these be more or less the same style as the calculus sequence? Sometimes it seems like all we do in calculus is more or less use integration/derivatives in different ways or extend them to multiple dimensions/multiple equations. How will the above classes be different is what I am wondering?