Font usage is one of the most important aspects of document exchange. If you expect a visually identical document to come out the end of an exchange process, you must pay attention to fonts. PostScript solves many of the practical problems of page layout. A page represented with PostScript is portable to any PostScript device. This is because PostScript is proprietary. Only one company, Adobe, licenses the technology. PostScript clones have now appeared and generally work quite well. One area of difficulty is that of font usage. When a PostScript document is moved from one machine or printer to another, it is important to know what fonts are available in the printer or system. If a font used in the original document is not available on the destination system, either you're out of luck or the font must be included with the PostScript file, which will increase the file size tremendously.
In the simplest case, a document composed with more than the four original Apple LaserWriter fonts cannot be printed on a LaserWriter unless the host machine also has that outline font available for downloading to the printer. As more and more fonts are used, the destination equipment, computer host, and printer must be contacted about font availability. Fortunately, once a particular font is identified as available, it should print just fine.
When you want to take a document to a service bureau for highquality printing, your choice of fonts better match what the service bureau can print. You can usually embed the fonts in the document, but you have to be conscious of these issues. The problem is worse now since the introduction of new font technologies, such as TrueType and Master Type. The service bureau must also have a collection of TrueType and Master Type fonts.
These problems are exacerbated when dealing with a WYSIWYG system. The fonts displayed on the screen are often special variations of the fonts used in the printer, and there are several flavors of screen fonts. Adobe solves the problem with Adobe Type Manager (ATM) available for both the Mac and PC platforms. ATM creates screen fonts from the same Type 1 format used for printing. TrueType, spearheaded by Apple and Microsoft, uses the same font description both for printing and display.