# What does velocity mean in motions graphs?

Velocity is the change in position occurring over a change in time. Change in position is known as displacement, and is represented by $\Delta d$, and change in time is represented by $\Delta t$, and velocity is represented by $\frac{\Delta d}{\Delta t}$.
In position vs. time graphs, time is the independent variable and is on the x-axis, and position is the dependent variable and is on the y-axis. The velocity is the slope of the line, and is the change in position/change in time, as determined by $\frac{{y}_{2} - {y}_{1}}{{x}_{2} - {x}_{1}}$ = $\frac{{d}_{2} - {d}_{1}}{{t}_{2} - {t}_{1}}$ =$\frac{\Delta d}{\Delta t}$.