PINK is one of the shortcut macros predefined in DefaultPreferences. See the section shortcut macros in that topic for a complete list of colors.
Syntax: %PINK% pink text %ENDCOLOR%
Expands to: pink text
%<color>% text must end with %ENDCOLOR%. If you want to switch from one color to another one you first need to end the active color with %ENDCOLOR%, e.g. write %RED% some text %ENDCOLOR% %GREEN% more text %ENDCOLOR%.