     Commands are your principal means of telling Multics what to do.  To
issue commands, you must have Multics at "command level".  Command level is
indicated by a "ready message" which looks like:  r 10:05 12.086 945.
Whenever you have such a line at the left hand side of the terminal screen,
just above the "cursor," you can type a command.

     Most commands take "arguments" that specify what they're to perform their
function on or how they're to perform their function.  For example, the print
command requires a "pathname" argument to tell it what to print.  The line:

print my_segment

invokes the print command to print the contents of my_segment.  An argument
that specifies how the command is to function is called a "control argument".
