TITLE: Difference between Slope and Gradient
QUESTION [20 upvotes]: It has been a few years since studying contour maps. 
Often I hear slope and gradient interchangeably in describing steepness.
Does anyone know any good definitions and analogies of slope and gradient.
Thanks,
Amanda

REPLY [2 votes]: Often I hear slope and gradient interchangeably in describing steepness.

This is because gradient and slope can mean the same thing. This depends on which part of the world you live in.

Gradient: (Mathematics) The degree of steepness of a graph at any point.
Slope:  The gradient of a graph at any point.
Source: Oxford Dictionaries

Gradient also has another meaning:

Gradient: (Mathematics) The vector formed by the operator ∇ acting on a scalar function at a given point in a scalar field.
Source: Oxford Dictionaries

Be aware that gradient can mean two different things in mathematics.