@Ryan
I suggest you read on a very simple mean value theorem first
http://en.wikipedia.org/wiki/Mean_value_theorem.
In the easiest way to explain, Taylor series is in its essense an attempt to approximate a function using polynomials, since polynomials are functions with very decent properties. It is used heavily in approximation theory or programming, not to mention it is a very useful analytic tool. If you want a decent explanation please tell me where can I find an online LaTeX render that'd produce a png or jpg I can post here (my last attempt was a failure unfortunately). Most proofs follow an induction step and it is best to see it that way, since the induction step in the proof is very similar to proof of mean value theorem. For more of course look up wiki:
http://en.wikipedia.org/wiki/Taylor's_theorem#Proof_for_Taylor.27s_theorem_in_one_real_variable
@ps
I did not read "For the win".
@Wrath:
Bonds as instruments of financial market carry risk much greater in comparison to government bonds, the government can always monetise their debt in need, while a CEO of a financial institution cannot print dollars out of thin air. Not to mention there are a lot of law requirements for some financial institutions to invest in government bonds.
@Ironheart
Shortest answer: capitalism. Short answer: communism is not actually an economic ideology, it is much more of a political ideology that fails on its premise by economic reality. In other words communism to me is not an economic ideology/structure in the same sense that in a communist society prices are not actual prices, only nominal values without carrying substantial economic information.