A coordinate system assigns an arbitrary point in space as the origin, and sets each axis at that point to zero.
In the world coordinate system, numbers increase from the origin to the right along the X axis, upward along the Y axis, and away from you on the Z axis. Numbers decrease (–1, –2, –3, and so on) to the left along the X axis, downward along the Y axis, and toward you along the Z axis. The distance between each whole number is called a unit of measurement (a 3ds Max unit).
Origin is the 0,0,0 point where the X, Y, and Z axes intersect.
You can combine the measurements of all three axes to mark specific locations in 3D space. The combined measurements are called coordinates. Thus, at the origin, the coordinates are X=0, Y=0, Z=0, which can be expressed more simply as the vector (0,0,0).
From the origin, the coordinates at a location 100 units to the right, 150 units up, and 60 units away are X=100, Y=150, Z=60, or (100,150,60).