Expands to: https://wiki.planta.de/twiki/bin/script
Example: To get the authenticated version of the current topic you can write %SCRIPTURL{"viewauth"}%/%WEB%/%TOPIC% which expands to https://wiki.planta.de/twiki/bin/viewauth/TWiki_/VarSCRIPTURL2
Note: In most cases you should use %SCRIPTURLPATH{"script"}% instead, as it works with URL rewriting much better