Plane Equation

Meaning of the coefficients

The vector [A B C] is normal (perpendicular) to the plane.
Thus, it defines the plane's orientation.

e.g.: A=1, B=0, C=0 defines a plane perpendicular to the X axis, or parallel to the plane of the Y & Z axes.
The plane equation in this case would reduce to x = -D.

D controls the distance of the plane from the origin. If [A B C] is a unit vector, then D is equal to the distance from the plane to the origin.