When you look out your window and see a skateboarder in front of your house and 2 min later you look out and see her several houses away you can use this information to describe her

this information describes her as skateboarding down the street.

The skateboarder's speed could have changed in the two minutes that you weren't looking out the window. Her velocity could have changed too, as well as her acceleration. The only thing that you know for a fact is her change in position.

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