Online help for CMS is available at both the DCL and the CMS
    subsystem command level. At DCL level, you can type HELP CMS or
    CMS HELP to get information. At CMS subsystem level, you can type
    HELP to get information. If you omit a parameter after HELP CMS,
    you get an overview of the CMS HELP facility. In this overview,
    the general syntax of a CMS command is displayed, and all the
    keywords for which you can obtain more information are listed.

    The command HELP CMS HELP gives a short explanation of how the
    HELP topics are organized.