* Motion: This is the act of changing position over time. It describes the *fact* that something is moving. It doesn't tell you *how fast* it's moving or in what direction.
* Speed: This is a measure of how quickly something is moving. It tells you the *rate* of change in position over time.
Think of it like this:
* Motion is like saying "The car is moving."
* Speed is like saying "The car is moving at 60 miles per hour."
In summary:
* Motion is a broader concept, simply indicating that something is changing position.
* Speed is a specific measurement of how fast that change in position is happening.
Speed is a way to quantify motion.
