The about context is the MAXScript equivalent of the rotate/scale center drop-down menu on the main MAX toolbar. It defines the center point about which any scale or rotation operation is performed within its context. Note that, like the center drop-down in MAX, this only sets the center point for the operation, not the axis. The axis is taken from the current working coordinate system set using the coordsys clause.
about selection
rotates/scales about the center of the current selection
about pivot
rotates/scales about each object's pivot point
about coordsys
rotates/scales about the center of the current working coordinate system set using the 'coordsys' context expression
about <node>
rotates/scales about the pivot point of the given object.
about <matrix3>
rotates/scales about the center of the coordinate system specified by the given 3D matrix.
about <point3>
rotates/scales about the given point with coordinate system and axes taken from the current working coordinate system.