# Definition of a Derivative

- Author:
- Phillip Clontz

- Topic:
- Calculus, Derivative, Limits

This page demonstration where the definition of a derivative comes from. Notice the variable "h" is the space between the two points (horizontally). As h gets closer and closer to zero the slope between the two points (x,f(x)) and (x+h,f(x+h)) becomes closer and closer to the slope of the tangent line at x. This is where the limit as h approaches zero comes from.