What information does the slope-intercept form of a linear equation reveal about a line

So, the equation for slope-intercept form is y=mx+b, with the main points being 'm' and 'b'.

M, is the slope. It determines the rise over run of the equation, otherwise said as the ratio of y over x.

B, is the y-intercept. It determines where the line crosses over the y-intercept. 

If M is negative, then the direction of the line will go from the top left to the bottom. If B is negative then the y-intercept has a negative value.