Grouping/Ungrouping, Joining/Seperating

When objects are grouped, they are linked together but they remain seperate objects. grouping is a frequently a convenient method for organizing objects and for allowing them to respond uniformily with certain operations.

When objects are joined together they become a single object, however, any intersections that may exist between objects are not revolved, and would have been done if a Bolean Union had been applied. The join operation is quite "liberal" and allows even objects of different types (i.e. solids, surfaces, and wires) to be joined into a single object. However, while this is convenient to do sometimes for rendering purposes, mixed type objects are restricted from many of the modeling operations.