Fundamental Theorem of Calculus Part I
If we had a function for the area, A, we could take the derivative to find a function for the height, y. This process is called differentiation.
Inversely, if we have a function for the height, y, we could take the ANTI-derivative to find a function for the area, A. Thus, for any function we can determine the area under its curve with the antiderivative. This process is called integration.