**Answer:** The **slope** of a line, often denoted by $m$, represents how steep the line is and in which direction it slants. It is defined as the ratio of the vertical change (rise) to the horizontal change (run) between any two distinct points on the line. Mathematically, for two points $(x_1, y_1)$ and $(x_2, y_2)$, the slope is $m = rac{y_2 - y_1}{x_2 - x_1}$.