What's the difference between speed, velocity and displacement?

Question

What's the difference between speed, velocity and displacement?

Answer 1

velocity is the first derivative of speed

and displacement is the first derivative of velocity or the second derivative of speed

Answer 2

speed is rate of motion

velocity is rate of motion with a direction/rate of change in position

and displacement is position of a point in reference to an origin point

Answer 3

Mojoeagle is correct and succinct.  Can't add more.

Answer 4

Speed is the rate at which distance is covered.

Velocity is speed AND direction

Displacement is distance covered from the original starting point.

Answer 5

velocity is both speed and acceleration and speed is just speed