1. The equation $y = mx + c$ is the equation of a straight line in slope-intercept form. 2. Here, $m$ represents the slope of the line, which indicates how steep the line is. 3. The slope $m$ is calculated as the change in $y$ over the change in $x$, often written as $m = \frac{\Delta y}{\Delta x}$. 4. The $c$ represents the y-intercept, which is the point where the line crosses the y-axis (i.e., when $x=0$). 5. This form is useful because it directly gives you the slope and intercept, making graphing straightforward. 6. To graph the line, you start at the point $(0, c)$ on the y-axis and then use the slope $m$ to determine the direction and steepness. 7. For example, if $m=2$ and $c=3$, the line crosses the y-axis at $(0,3)$ and rises 2 units for each unit it moves to the right. 8. The general form makes solving linear equations and understanding linear relationships easy and intuitive.