A role-playing game (RPG) is part improvisational theater, part story telling, and part board game. It is played by a gamemaster (GM) who runs the game and a group of players who pretend to be characters. These characters are defined by a set a statistics that represent skills and attributes developed in the character creation process. These are fleshed out with an invented background and personality. The GM presents the setting and situation; through their characters, the players interact with the story line and other characters.
Imagine a movie where the characters did things you thought were utterly stupid. No amount of yelling will change the character's mind; you are along for the ride. In an RPG the players control their characters' actions and respond to the events of the plot. If the player does not want his character to go through the door, the character will not. The script or plot of an RPG is flexible and always changing based on the decisions of the players' characters.
The GM controls the story. He or she keeps track of what is supposed to happen when, describes events as they occur so that the players (as characters) can react to them, keeps track of other characters in the game (refereed to as non-player characters or NPCs), and resolve attempt to take action using the game system. The game system is used when a test is required to see if an attempt to perform a specific action was successful, generally, by rolling dice. Each RPG has a different method of determining success.
Our role playing group originally met as the Midieval History Club, though some us knew each other before. The first RPG we played together, and the first I ever played, was Rifts from Palladium Games, GMed by . After that, we moved onto Cyberpunk 18.104.22.168. from R. Talsorian Games. These games are GMed by . Then I decided try GMing also, so I started up a game of Shadowrun from FASA.