Most desktop publishing software allows for grids in the form of a page filled with coloured lines or dots placed at a specified equal horizontal and vertical distance apart. Automatic margins and booklet spine (gutter) lines may be specified for global use throughout the document. Multiple additional horizontal and vertical lines may be placed at any point on the page. Invisible to the end-user/audience shapes may be placed on the page as guidelines for page layout and print processing as well. Software templates are achieved by duplicating a template data file, or with master page features in a multiple-page document. Master pages may include both grid elements and template elements such as header and footer elements, automatic page numbering, and automatic table of contents features.