Speed is a matter of how fast an object is moving regardless of the direction it's going, whereas velocity is a matter of how fast an object gets somewhere with respect to direction.
Velocity is a measure of how quickly an object moves. So, the velocity is the change in the position of an object, divided by the time. Velocity has a magnitude (a value) and a direction. The unit for velocity is meters per second (m/s).
v= ( Xf - Xi ) / t
v = velocity (m/s)
xf = the final position (m)
xi = the initial position (m)
t = the time in which the change occurs (s)
Δx = short form for "the change in" position (m)