Coordinates in 3D

The most basic visual entity in the 3D space is the point. The point has no size, but it does have a location. To determine the location of a point, first establish an arbitrary point in space as the origin.

X, Y, and Z Axes

We can say a point's location is:

The three dimensions are the X axis, the Y axis, and the Z axis.

 

The point on each axis is represented by a number, and the point in space is expressed as the three axis numbers in XYZ sequence. This gives the 3D coordinates of a point in space.  The point of origin is always expressed as (0, 0, 0).  Where the three axis coordinates intersect, we have the coordinates in the 3D space.

World Space, Object Space, and Local Space

3D positions and transformations exist within coordinate systems called spaces.

See also:

3D Viewport Overview

The X, Y, and Z Axis Legend in the 3D Viewport

Pivot Point Used in 3D