All the geometry of your drawing is contained in layouts. Model space geometry is contained on a single layout named Model. You cannot rename the model space layout, nor can you create another model space layout. There can be only one model space layout per drawing.
Paper space geometry is also contained on layouts. You can have many different paper space layouts in your drawing, each representing a different configuration to print. You can change the name of the paper space layouts.
In ActiveX. Automation the ModelSpace collection contains all the geometry in the model space layout. Because there can be more than one paper space layout in a drawing, the PaperSpace collection points to the last active paper space layout.
For more information about working with paper space layouts, see â€śHatches, Fills, and Wipeoutsâ€ť in the User's Guide.