|File Type||Rez Source Code File|
|File Format||Proprietary (Apple)|
|Usage||Open manually; may be referenced by an application|
|Popularity||★ ★ ★ ★ ☆ Common|
Resource file that may be referenced by one or more programs in Mac OS X; typically contains variable definitions and short functions; may also reference other resource files.
R files in Mac OS X are similar to .RSRC files used in Mac OS Classic.