This is where I don't know what to say, other than the whole world is based on it. There are numerous topics on the subject of mathematics that one can never get tired of learning all about them and open some more of their mind. Well, enough with the philosophy, still there are many different topics in mathematics that a FE examinee should understand in order to do well on this section of the exam. I have learned all these topics a long time ago, that seems too vague to me to say I know them. I guess I will have to re-learn them all and I think I'll probably enjoy it too. So, here we go:
"The laws of nature are but mathematical thoughts of God" -- Euclid of Alexandria, the Father of Geometry