Several RhinoScript methods either require as an argument or return as a result a plane.  Planes are represented as zero-based,  one-dimensional array containing four elements: the plane's origin (3-D point), the plane's X axis direction (3-D vector), the plane's Y axis direction (3-D vector), and the plane's Z axis direction (3-D vector).

Planes can be constructed in a number of ways.  For example,

Dim arrPlane(3)

arrPlane(0) = Array(0.0, 0.0, 0.0) ' origin point

arrPlane(1) = Array(1.0, 0.0, 0.0) ' x-axis vector

arrPlane(2) = Array(0.0, 1.0, 0.0) ' y-axis vector

arrPlane(3) = Array(0.0, 0.0, 1.0) ' z-axis vector

Planes can also be created using the PlaneFromFrame, PlaneFromNormal, and PlaneFromPoints methods.

RhinoScript contains a number of methods to manipulate planes.  See Lines and Planes for details.