Mac OS X applications typically store preference settings in plist files, such as "com.apple.Mail.plist". In Mac OS X 10.3.9 and earlier, plist files were typically in XML format. In Mac OS X 10.4 and later, plist files are often in binary format for faster application performance.
Important: You should not usually modify preference files directly. Instead, you should use the associated application's Preferences menu(s) to customize your settings.
In certain situations you may need to read preference files directly using one of the following methods.