The DM provides the gaming environment, the details of the adventure and even sets the atmosphere. It is not the DM's goal to pit him/her self against the players, but to create the game as it's own thing.
After the DM has created the "game field" so to speak and the Players have their characters created and ready to enter said "game field" or as I like to refer to it, the "Arena", it is on!
The DM becomes arbiter of rules/referee and role-player of NPC's. The GM also tracks things and does what is required to keep the game moving along.
So what is it the players are really doing then? As someone put it in a forum post, they are the story. The choices they make, the things they do as they play the game is the stuff of legend. The game itself is the setting for epic tales to be told.
The Players, via their PC's, take risks, face consequences and reap great rewards or suffer dismal failures.
The DM, in short, IS the Game. The Players are the Story. Together, they are a super-organism. One cannot exist without the other.
A DM with no players is merely a dream. A Player with no game to play is just a figment of imagination. Put the two together however and you have something that becomes more than the sum of it's parts.
This is why a DM must work carefully to create a game to be played. Sometimes a GM will create an elaborate, detail rich game ad ends up creating the story along with it. Then they don't want the players to come in and "ruin" their tapestry and place so many limitations and instead of providing guides and paths and clues for the Players to follow and pick up on their own.
The DM nearly drags them through the game making the Player more of a bystander or suggestion maker than really allowing them to be a Player. That's no fun in he long run for anyone and that's not a game so much as it is a "pick your own ending" story.
Conversely, it wouldn't be much of a game if paths weren't followed and leads not pursued. The Players have to "buy in" and actually play the game as it is presented by the DM.
DM's have a variety of game styles they can present.
- The Dungeon Crawl Game. Draw up a dungeon, roll randomly to place monsters and treasure, traps and tricks into the dungeon and let the players go in and wander around. Your average dungeon crawl.
- The Plot Thickens Game. Give the players a mystery to solve. Provide them with clues and lots of places to investigate. Throw in false leads, rumors and speculation. Toss in some plot related encounters along the way and rescue the girl or find the treasure or get rid of the bad guy.
- The Random Game. I like to do this every so often. Literally everything is completely random and you make it up as you go. You roll for just about everything. Have a few "blank" random dungeons or adventure areas set out and as PC's find their way to and enter them, populate them as they are entered.
It' s one thing for a Player to give a friendly reminder or to ask for a second look at a rule. it's another thing altogether to argue, debate or challenge and become a rules lawyer while the game is on. That's just being obnoxious and is un-called for.
For DM's, a game should be challenging, but not impossible. Give the players a chance to play. If there's any one thing Gary Gygax did make perfectly clear in the AD&D 1E books (and there's not many) is that the rules are rules only so long as it furthers the playability of the game. It is your game DM. You decide what rules need to be followed to the letter, if any, and what rules are holding the game back.
One opinion Gary Gygax expressed that I do agree with is that in the end, this is just a game. It does not and should not mimic reality to the point it becomes a re-enactment or a combat simulation.
It' s about getting some folks together and blowing off some steam, having some fun and matching wits against imaginary adversaries.
What more could you ask for? (if you say food and drink, that can be there too, but at my games it's potluck and/or BYO ;) )