What are we playing?I usually talk about my hobby using the term "roleplaying games", but there are some other terms that we could use: adventure games, and storytelling games.
The Alexandrian has already blogged extensively on the differences between Storytelling and Role-playing games, so I won't repeat what he's said in depth - but I think we should add this other category, adventure games, which he doesn't cover.
An adventure game at first may look a lot like a role-playing game: the players assume roles in the game, and overcome obstacles. The difference is in the lack of alter-ego - the player's character is primarily an avatar of themselves; there is no attempt to portray a separate character.
Adventure games rely on the players' abilities - it is the player that solves puzzles, investigates scenes, and explores.
In the classic text adventure, The Hobbit, you may be following the story of the protagonist of the book of the same name, Bilbo Baggins, but the game doesn't expect you to take choices based on your attempt to portray the famous halfling. You are expected to solve problems and achieve goals by making winning moves.
Similarly, in Tomb Raider, you control Lara Croft, aristocratic archeologist (and exterminator of endangered species) - but you proceed through a series of challenges and puzzles, rather than trying to act out the behaviour you judge to be likely for such a character.
As a player of adventure games, it is your insight and skill that drives your character / avatar forward, not those of the character.
Adventure games use story and character as background for puzzles and action.
By contrast, role-playing games manifestly expect us to adopt the behaviour of our characters. Our goal is increasing the power of our characters through experience - gaining treasure, skills and prowess. Acting out the actions that our character would take, based on our assumed character identity - and the fallout and consequences of those actions - is the entertainment at the heart of role-playing.
Role-playing games use story, puzzle and action as a background for character progression.
Storytelling games focus on narrative. In storytelling games, it is often better to take actions that you, as the player, know will put your character at risk in order to progress through the story. Preserving your character becomes secondary to the story - dramatic situations are more important than amassing character power.
Storytelling games use action, puzzle and characters as devices to move the story forward.
Blending:In actual play, games tend to be blend of the above.
Players may need to feel that their insight and skill is useful - adventure game style. If character skill totally overrides player skill, this can be frustrating. Consider video game characters who cannot climb over simple obstacles. Conversely, characters who achieve actions utterly unheard of by the players - interpreting clues without a clear logical path, for example - can make players feel they are being led by the nose, or "railroaded".
Storytelling requires characters to take actions that stretch reality - investigating the noise in the cellar with a faulty torch in one's night clothes, or speaking aloud the arcane inscription on the profane temple altar. These actions move the story along.
It need not be as extreme as that, of course, but for the sake of the game, characters sometimes need to take on tasks that are outside their comfort zone.
"My character wouldn't do that" means that the game stops right there for you. A blunt GM might say, "Fine: fetch me a character who will," or even, "Fine: your character sits in his apartment while the rest of the player characters go on their adventure."
So for a game - whether that's an adventure, role-playing or storytelling game - to succeed, you need to consider all of the styles.
An adventure game dissolves into a series of dry IQ tests if there is no story or character to motivate the players.
A role-playing game needs both story and obstacles that are interesting, or it'll end up just being a grind of killing wild boars till you level up.
And storytelling games can become ridiculous if the character's actions or the obstacles presented are too unbelievable.