Online help for MS Windows - most commands will give help when run with /? or -? (COMMAND /? or COMMAND -?)
GUI Help is available from START - Help or by running the help files directly:
Syntax WINHELP [options] helpfile.hlp WINHLP32.exe [options] helpFile In XP: C:\WINDOWS\PCHealth\HelpCtr\Binaries\HelpCtr.exe options: -H show help about help -G[n] Build a .gid file and quit, If a number is specified, it determines which extensible tab to display by default the first time the help file is opened. A value of 1 would be the first tab beyond the Find tab. This command cannot be used with -S. -S Create a .gid file without showing an animated icon. Cannot be used with -G. (winhlp32 only) -W window Specify the window for displaying the topic. This command cannot be used with -P. -P Show the topic in a pop-up window. This command cannot be used with -W. You must use the -P switch in combination with the -N (context number) or -I (topic ID) switch. -N contextNum | -I topicID Specify the topic to open using either a topic number, (defined in the [MAP] section of the HPJ file.) or a topic ID string (# footnote in the topic). -K keyword Specify the topic to open using a keyword. This command cannot be used with -N or -I.
Powershell: Get-Help - Open the help file