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If you want to use non-default fonts with TeX, to install additional font packages or to set-up and install arbitrary fonts for use with TeX, this is the place to start. You can find samples of many standard TeX fonts with links to information about how to use them in your documents. Many of these fonts may already be installed and only require a line or two to be added to your document. You can also find samples of additional fonts and information about downloading and installing the TeX-ready packages available. Finally, if you have some font that you simply have to use with TeX, you can find details of the obstacles you are likely to encounter and strategies for overcoming them.
Font display issues
A common problem with the display of TeX-generated PDFs on Mac is font display issues. This will be resolved in the 2009 TeX Live release. In the meantime, a patch is available for the 2008 TeX Live release which will reduce the bug's occurrence for most users. Please see the Font Cache Bug.
The display problems are caused by PDFs which corrupt the font cache. Whether or not you have installed the available patch, deleting the font cache can solve the problem once it has occurred. An easy way to do that is to use Onyx.
By default, most typesetting will use the Computer Modern fonts. The bitmap version of these fonts was specifically designed for use with TeX and typesetting originally required fonts to be in this format. Unfortunately, such fonts can look ugly on-screen if the viewer does not support them properly (although they will still look fine printed), so another font format is often a better choice. Today it is possible to use several other font formats with TeX and most current installations will therefore use one of the available postscript versions of Computer Modern by default.
In most cases, installing a font in /Library/Fonts or in your personal Fonts folder is not sufficient to enable the font for use with TeX. An exception to this is the use of the XeTeX engine which can use many fonts available to Mac OS X directly. See Using fonts with XeTeX for details. To use a font with any of the other engines, the font must be installed for use by TeX along with an appropriate set of support files.
Although it is theoretically possible to use most fonts with TeX, certain typefaces and fonts are particularly well-suited to the task. Some have been specially designed for use with TeX. Others have specially designed support packages. Sometimes such fonts include symbols useful in TeX but typically missing from other fonts. Others are designed for typesetting mathematics or logic.