You can click on this link to have your Web browser show you the sizes of the various graphics files referenced on this page. Note that the sizes of the GIF image files of each overhead are fairly consistent, usually several kilobytes. The PostScript file sizes are wildly variable; a very simple page description like ``communicate.ps'' can be only a few kilobytes, smaller than the GIF version. A very complex page with thousands of graphic elements, like ``outline.ps'', can be 650 kilobytes. For most of these pages, the compression inherent in the PDF format preserves all the information in the graphical elements, with a size saving of 50% to 80%.
As rasterized image files, of course, the GIF versions preserve little of the information in the original graphic elements. If you compare some of the PDF or PostScript pages with their GIF versions, you will notice that some of the smaller and less bold graphics are invisible in the GIFs.