I have a project that started this week. A friend of mine wrote a Role-Playing Game system several years ago, he's a genius and his system is the best I've ever come across. I don't say this lightly because I'm a huge critic when it comes to RPG's. Despite my love for them I'm very particular about the one's I bother with.
A role-playing game (RPG) is an interactive story where the players take on the 'role' of individuals within that story, interacting with it as the plot progresses. The individuals that the players take the roles of are called Player Characters (PC's). Players act out their PC's actions, and dialog much like an actor would in a play or movie.
This is the most simple definition of a Role Playing Game, there are many variables. Some are pre-scripted as a computer program and characters are animated to be played on a computer game or console. But others, the original Role Playing Games, are played out with a person running the game called a Game Master (GM) who tells the story while the PC's interact within that story in person and face-to face. The difference between these two iterations could be likened to playing a game of online poker, and playing cards around a table with friends.
Like a card game, a role-playing game has rules and items integrated into it's gameplay. These rules are designed to act as a framework to determine whether or not a given action in the game is successful or not. Usually dice are used to randomize the results of these actions, adding uncertainty to the outcomes and making things exciting. Through the rules of the game the Players and Game Master can interpret the results of the actions within the game and the game master then rationalizes how these results effect the PC's while the PC's react to these effects.
And now… I give you a bit of music that's keeping me going right now.