Calculus, made visual
The payoff of the whole ladder: see the derivative as a slope and the integral as an area, watch them turn out to be inverses, and reach all the way to approximating any function with a Taylor series.
Module 1 · The derivative
Module 2 · What the derivative tells you
Module 3 · The integral
Module 4 · Integration: techniques & applications
Module 5 · Sequences & series