The OSF/Motif Window Manager (mwm) is an X11 client that manages the appearance and behavior of objects on the root window.  You control mwm and its management operations using a mouse, a keyboard, and a functional window frame.  Additionally, mwm has a root menu to assist you in the general control of the root window. 
The OSF/Motif Window Manager is the default window manager for your X Window System.  It is started from $HOME/.x11start when you start X11.  If
that file doesn't exist, mwm is started from
sys.x11start in 
/usr/lib/X11.
The syntax for mwm is as follows: 
where options are: 
- -display host:display.screen
 Specifies the screen to use.
- -xrm resourcestring
 Specifies using the named resource on starting.
- -multiscreen
 Causes mwm to manage all screens on a display.  The default is to manage only a single screen.
- -name name
 Uses name to retrieve resources.
- -screens name [name ...]
 Gives the resource names for the screens managed by mwm.  The names are separated by spaces. 
The following line in .x11start in your home directory starts mwm.
The $@ passes the window manager options specified on the x11start command line.