OS X manages fonts in multiple locations in support of its design as a multi-user system. This new capability, which most people do not use, adds complexity to a familiar task. To further complicate matters, different font folders may have different permissions; there is also a new class of system fonts, and support for Unicode (a good thing). If your work makes extensive use of fonts, an understanding of how OS X manages them is essential.

Font search order
When searching for a font, OS X uses the first font name match it finds, searching font folders in the following order.

 Application fonts. Some applications have their own font folder. For that application only, fonts stored in the font folder will take precedence over other fonts on the system.

/Library/Fonts is intended for shared fonts. Unless you are sharing your computer, do not put fonts here.

/System/Library/Fonts holds essential fonts the system needs for menus and dialog boxes. To delete these fonts, you will need to change the permissions on the folder.

/User/your_username/Library/Fonts holds your personal fonts. This is the place to store your fonts, unless you are using Suitcase. If you are using Suitcase, organize your fonts in a new font folder, with a name such as 'My fonts,'  in your /username/Library.

Classic System/Fonts.  Classic applications require fonts in the Fonts folder in the Classic System/Fonts folder.

Network/Library/Fonts (when available) is located on another computer on the network. Unless you are sharing fonts across the network, you may ignore this folder.

Required fonts
Operating systems require certain fonts to display menus, dialogs, etc. You can remove all the fonts that were installed with the OS excepts these required fonts.

OS 9 required fonts
Unless you need to work with fonts in a Classic application, you may delete all fonts in System/Fonts except:

               Charcoal
               Chicago
               Geneva
               Monaco
               New York

OS X Required fonts
- You may delete all fonts from /Library/Fonts (shared fonts)
- You may delete all fonts from Users' Library folders. This assumes that other users were defined on your system, and you no longer want their fonts.
- Do not delete these fonts from /System/Library/Fonts:

Apple LiGothic Medium.dfont
AppleGothic.dfont
AquaKanaBold.otf
AquaKanaRegular.otf
Geneva.dfont
Keyboard.dfont
LastResort.dfont
LucidaGrande.dfont
Monaco.dfont
Hei.dfont
Helvetica.dfont 

You may delete Hei.dfont and Helvetica.dfont, but only if you install Postcript or TrueType versions of Helvetica or Helvetica Neue.

Removing fonts
You may want to remove unneeded fonts or OS X system fonts which have the same name as Postscript or TrueType fonts you own, such as Helvetica, Times, Zapf Dingbat and Symbol.  It is best to remove fonts into a 'removed fonts' folder rather than deleting them. You will need to change permissions to remove /System/Library/Fonts.

1. Select the Fonts folder within the System/Library folders.

2. Press Command-I.

3. Open the Ownership & Permissions tabs

4. Click on the lock icon.

5. In the dialog box, enter your administrator password.

6. Change the owner in the pop-up from System to your login name and '(Me)'

7. Make changes in the folder.  

Fonts types supported
OS X supports the following type technologies.

 PostScript fonts are used for high-quality print output. Each PostScript font requires two files, one for the screen font and one used by the printer.

 Multiple Master is a type of PostScript font which generates variations, such as font weight or style, from a single instance of the font. It is a font technology that never took off.

 Mac TrueType Unlike Postscript, a single TrueType file contains both screen and printer font information. Although many designers still prefer Postscript, most TrueType fonts are of high quality. The extension is .ttf. 

Windows TrueType Like Mac TrueType, the extension is .ttf.

 dfonts are OS X System fonts. A type of  TrueType font that contain information in the data fork instead of in a separate resource fork, they are of high quality, but may have naming conflicts with installed PostScript or TrueType fonts. If so, you may remove them.

 OpenType (.otf) are a new font format which takes advantage of Unicode. Because they can contain 65,000 different glyphs, these fonts have particular value for non-Roman languages such as Chinese or Japanese

 

International keyboards may be activated for foreign language input in System Preferences/International/Input Menu. The two font utilities listed below may also be activated in the same preference dialog. Both show up in the Keyboard menu, not as independant applications.

Keyboard Viewer shows keyboard layout and character mappings for each font. It allows insertion of selected characters into documents.

Character Palette is a character map for Unicode. In addition to displaying characters in a Unicode table, it displays categories of charcters and the installed fonts that contain them. Characters can be inserted into applications that support Unicode.