@appendixsec X Resources
@cindex resources
+@cindex X resources, @file{~/.Xdefaults} file
Programs running under the X Window System organize their user options
under a hierarchy of classes and resources. You can specify default
values for these options in your X resources file, usually named
(optionally even for all programs).
@cindex Registry (MS-Windows)
+@cindex @file{.Xdefaults} file, and MS-Windows
MS-Windows systems don't support @file{~/.Xdefaults} files, but
Emacs compiled for Windows looks for X resources in the Windows
Registry, under the keys @samp{HKEY_CURRENT_USER\SOFTWARE\GNU\Emacs}