Projects can directly contain many workplanes. Workplanes are shown in the Explorer under the Workplanes branch of the tree.
Workplanes are controlled by menus. Workplanes define the coordinate system that is used to create a toolpath.
When there is no active workplane, the Active Axes in the bottom left of the screen represents the transform or global coordinate system. When there is an active workplane the Active Axes represents the active workplane.
When representing the global transform the principal editing plane axes are white (if pointing towards you) 
, grey (if pointing away from you) 
, and the normal to the principal editing plane is cyan.
When representing the global transform the principal editing plane axes are red and the normal to the principal editing plane is cyan 
.
Display of the Active Axis is controlled using Draw > Active Axes.
The axis is bold and bright if pointing towards you and muted and thin if it points away 
.