Here's the breakdown:

* Speed is a scalar quantity, meaning it only has magnitude (size). It tells you how fast something is moving. For example, a car traveling at 60 mph has a speed of 60 mph.

* Velocity is a vector quantity, meaning it has both magnitude and direction. It tells you how fast something is moving and in what direction. For example, a car traveling at 60 mph east has a velocity of 60 mph east.

Think of it this way:

* You can run at a certain speed (e.g., 5 miles per hour).

* But you could be running at that speed in different directions (north, south, east, west, etc.). This change in direction changes your velocity.

In summary:

* Speed is how fast something is moving.

* Velocity is how fast something is moving and in what direction.