LEVELS allows you to separate a part into different layers
or overlays. Each layer can be manipulated individually or
with other layers.

Basic level management capabilities include:

- The ability to specify or change level assignments at 
  any time.

- The ability to turn the display of any level or
  combination of levels on or off.

- The ability to move or copy entities from one level to
  another by selection or level specification.

NOTE: When using LEVELS, keep in mind that if the active 
level is not already displayed, it is added to the 
system's display list of levels. This is a convenient 
way to separate a part (or drawing) into layers that can 
be displayed, plotted, and operated on independently of
each other.

Choose from the following LEVELS options:

ACTIVE - to choose the level to which newly created
         entities are assigned.

ADD    - to turn levels on within the current display.

REMOVE - to turn levels off within the current display.

MOVE   - to transfer entities from one level to another.

LIST   - to list all level numbers on the screen and to
         toggle desired levels on or off.

MASK   - to screen out active levels in the current part.

NAME   - to attach descriptors to all levels from within
         CADKEY or from an ASCII text file, generate an 
         onscreen listing of all level descriptors, and 
         write the current descriptors to an ASCII text 
         file.

There are 256 levels from which to select. However, level
number 256 is reserved for storing entities which you
choose not to displayed. When this level is activated,
entities can be selected even though they are not viewed
in the display. To display the contents, you must move the
entities on level 256 to an active level.
