* Velocity is a vector quantity: Velocity includes both speed (how fast an object is moving) and direction.
* Speed is a scalar quantity: Speed only describes how fast an object is moving.
Examples:
* A car driving around a circular track at a constant speed. Even though the car's speed remains the same, its velocity is constantly changing because its direction is changing.
* A ball thrown straight up in the air. As the ball travels upwards, its speed decreases, and its velocity changes. At the peak of its trajectory, its speed momentarily drops to zero, but its velocity is still changing as its direction reverses.
In summary: A constant speed doesn't guarantee constant velocity. For velocity to remain constant, both speed and direction must remain unchanged.
