# Queries regarding Newton's method

I am currently trying to study the Newton's method of optimization through this wiki article http://en.wikipedia.org/wiki/Newton%27s_method_in_optimization. However, I didn't get this concept about constructing the sequence xn and approximating the objective function by a quadratic function around xn.

Can anyone provide me some good references. I mean why are are constructing that sequence xn? Any geometric visualization will be helpful I guess.

-