Here we introduce Primary Face, Secondary Face, Foot Prints, Touch Types and the importance of Part Names.
When a part is created there lies a point in the part called the centroid. The centroid is the centre of mass of the part, if we were to suspend this part from a string attached to the centroid it would remain perfectly in balance.
Creating an assembly of these parts to make a cabinet also creates an assembly of centroids. The amalgamation of these centroids then creates a common point known as the centroid of the cabinet, and generally lies inside the cabinet.