MSCAD 2005: Externally Referenced Drawings - XREF

MSCAD2005 treats an xref as a type of block with some important differences. When
you insert a drawing as a block, it is stored in the drawing and is not updated if the
original drawing changes. When you attach a drawing as an xref, you link that referenced
drawing to the current drawing; any changes to the referenced drawing are displayed in
the current drawing when it is re-opened.