Help and Support Center is the unified Help introduced by Windows XP.

The application also registers the pluggable protocol "hcp://", which may be used to launch the help center from a web site. It is also used for navigation within the center itself. The path and file specified in an URL when using the hcp protocol may specify a file to open relative from the HELPCTR directory. ie. The URL "hcp://system/sysinfo/msinfo.htm" will launch
the Help Center and open the file "%windir%PCHEALTHHELPCTRSystemsysinfomsinfo.htm".

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