DOOM I

IDDQD = Toggles the God Mode On/Off
IDKFA = Gives You All The Weapons, Keys, Ammo, and 200% Armor
IDFA = Gives You All The Weapons, Ammo and 200% Armor

IDBEHOLD + Following
S - Get Beserk Strength
V - Temporary Invulnerability
I - Temporary Invisibility
A - Get Full Automap
R - Get Anti-Radiation Suit
L - Light Amplification Visor

IDSPISPOPD = Toggles The Clipping Mode
IDCHOPPERS = Get The chainsaw and a Message!
IDCLEV = (Episode #) (Map #) - Level Warp
IDDT = Toggles between normal map, fullmap, and fullmap + objects
IDMYPOS = Displays coordinates and heading


DOOM II

IDDQD = GOD MODE
IDKFA = ALL KEYS AND FULL AMMO
IDCLIP = WALK THROUGH WALLS
IDMYPOS = CO-ORDINATES
IDDT = MAP ADD ON
IDCHOPPERS = GIVES YOU A CHAINSAW
IDG Effect = GRID MODE (Makes lines Go on the map). Type it at the map 

For NetWork cheat:
In map mode, hold down ALT and type IDDT 4 times

DeathMatch cheat:
Go into your map and type T for talk mode. Hold down ALT key and type IDDT several times. And 
when all of your map comes up, repeat again once to see all items and again to put it back to 
normal. This does not work with the other cheats by holding ALT.

* = works on DOOM as well.
*IDDQD= God mode.
IDCLIP= Walk through walls.
*IDCLEV= [MAP NUMBER].
*IDKFA= All weopons and keys.
IDFA= Reset ammo.
*IDSPISPOPD= Only for doom not doom2= clipping.
*IDCHOPPERS= Says this message and gives you chainsaw.
*IDMUS {LEVEL NUMBER} = to switch to that levels music.

*IDBEHOLD<Letter> = Press these when you type in idbehold.
   I for invisible.
   A for all map.
   V for a that green face bonus. Kind of like god mode.
   S for beserk, one cool chuck style.
   L for light amplification.

*Idmusic= This is how you exit when level= ic