X fonts are files installed separately from printer and wysiwyg fonts.
To add new X fonts.
X and printers have their own fontsets.
Most printers have a raw mode, in which they accept an ascii text file. Even though the screen presentation of the file may have included bold and italics, the raw print will be unvaried.
Most home and small business systems print each page as a 60 Kbyte bitmap. A well-featured, and thus not compressible, page will require about 1 minute just to transmit to the printer at 9600bd.
Businesses that often need to print more than 60 pages per minute use a line printer. Most line printers cache a small number of fonts which which may be in rom or loadable into ram. While printing is limited to the cached fonts, only the 30x smaller raw file need be transmitted.
Many home and small business systems use ghostscript to generate the printer page bitmaps. In order to do so, ghoscript needs fonts installed. Ghostscript-7.05 can only parse Postscript Type1 fonts, so other font formats must be converted before installation.
Web pages show squares instead of readable text. Tabbed text in documents doesn't line up.
The X server and X clients have their own fontsets.
The X server and X clients can send bitmaps back and forth, but usually send character codes. Sending character codes increases performance by an order of magnitude or more, but results in image differences if the server and client don't share the same fonts.
On the same host, the X server and X clients can usually read the same font files. On different hosts, font files need to be copied as necessary to have the used fonts available on both hosts. Between different hosts, the X protocol supports an optional X fontserver, but most distros do not configure the fontserver by default.
Fonts are used for many purposes than conveying textual information. They can also convey emotion, context, and properties like urgency. Take a look at your next bill. Disclosures will usually be in sans-serif non-proportional fonts (called fine print) that are harder to read. Inducements are usually in serif proportional fonts which are much easer to read.
A lot of psychological research goes into the development and selection of fonts. A monopoly of a decade or two is a constitutional (Constitution of the United States Article I Section 8) reward for that effort.
Laws require or prohibit font usage in such situations as warning signs like DYNAMITE or HIGH VOLTAGE. Other laws set minimum and maximum font sizes in contract disclosures, or advertising. Trademarks like Nutrition Facts define fonts to prevent deception.
Students should be familiar with using X executables and selecting fonts in at least one executable, e.g. gimp.
If feasible, student should plan to bring a laptop equipped as follows.
Student should snapshot XF86Config.
Student should load POSTNET.ttf provided by the instructor.
Practice adding new fonts.