- There are two basic types of macros:
  Home Macros
    Reside in the directory set by the `HOME` command (typically the home directory of the user).
    Run by preceding the macro name with percent (`%`) character at command line.
    Home macros are commonly called Percent Macros and occasionally called User Macros.
  Installed Macros
    Reside in the `mcr` area of an option tree.
    Installed by adding the macro to the command dictionary.
    Have their own explain files.
    Will show up in the list of commands generated by the `MENU` command.