Position

Position is commonly expressed as as $x$ , $(x,y)$ or $(x,y,z)$ .

The position $x$ is located on a line. We could use a ruler as an example.

A position $(x,y)$ is located on a grid.

A position $(x,y,z)$ is located in a 3D space.

The word Position is synonymous with Location.

Distance is a subtraction of one position from another position.

Distance on a number line = $x_2 - x_1$

When two or more dimensions are present, we take the square root of the sum of the squares of the differences:

Distance in 2D space = $\sqrt {(x_2 - x_1)^2 + (y_2 - y_1)^2}$

Distance in 3D space = $\sqrt {(x_2 - x_1)^2 + (y_2 - y_1)^2 + (z_2 - z_1)^2}$

Distance is also called Length.

Appendix A

Velocity is a Change in Position divided by a Change in Time:

$v = \dfrac {\Delta x} {\Delta t}$