Using a spell, darkfire torch or object to lower the light level in a 
room.  Newbies can ask their guide about dark, other players must use a 
spell or item to achieve lighting change.  To check your racial light 
requirements, you can check the help file for your particular race.

To get a list of the various light levels: 
HELP LIGHT LEVELS

SEE ALSO: help spell darkness, help light