-cvar_t skill = {0, "skill","1"};
-cvar_t deathmatch = {0, "deathmatch","0"};
-cvar_t coop = {0, "coop","0"};
+cvar_t skill = {0, "skill","1", "difficulty level of game, affects monster layouts in levels, 0 = easy, 1 = normal, 2 = hard, 3 = nightmare (same layout as hard but monsters fire twice)"};
+cvar_t deathmatch = {0, "deathmatch","0", "deathmatch mode, values depend on mod but typically 0 = no deathmatch, 1 = normal deathmatch with respawning weapons, 2 = weapons stay (players can only pick up new weapons)"};
+cvar_t coop = {0, "coop","0", "coop mode, 0 = no coop, 1 = coop mode, multiple players playing through the singleplayer game (coop mode also shuts off deathmatch)"};