A subpage is a part of a logical page on which line data may be placed. Subpages are used only with conditional processing. Multiple-up printing can be done with or without subpages being defined. In the page definition, multiple subpages can be placed on the physical page based on changes in the print data. A good example of this is the use of multiple-up printing, which is printing two or four pages on a single side of a sheet. For more information, see Subpage Description and Processing.