I have sometimes struggled with that very question though: what is an RPG? What constitutes the decision for some to say "well this game is not an RPG, but this one is?" And for me, it all started back in the old forums. Some people were saying "Oblivion is not a role-playing game", which sort of hurt my feelings because I'd put so much love into that game! I certainly thought I was playing some roles with my myriad assortment of characters. How dare they!

But it also made me think. Why would they come to this conclusion?
For a lot of Morrowinders especially, the answer is "there is more of a separation between player and character skill." A lot of features (such as repairing items, unlocking stuff, and even casting spells) are based on character skill, not the player's ability to be quick enough with those joysticks, or that mouse. To them, the definition seems to lie somewhere in this greater separation of toon versus player.
Well my definition is simpler: an RPG is a game in which the focus is playing a role in a game. Not the action. Not the quests. Not the adventures. Not even the dice-rolls. Or the classes. Or any of the numbers. All of those are incidental. Although I do consider all of those features to be essential toward making a good RPG, what exactly does this term boil down to?
It is game which allows us to play a role, in which the focus is playing a role (rather than THE role).
In other words, let's say the only thing we could do in any Elder Scrolls game (or Fallout) are the Main Quests. We can't explore. We can't make potions. No side quests. No guilds. No factions. Only the good guy or gal (which we play), the enemies, and occasional NPCs who help us further the Main Quests. We can't gaze at awesome sunsets. We can't strip our characters down and go for a swim. If this is all Bethesda allowed, without even the character progression noted in Bioshock or Dragon Age (I assume), well that to me would make Bethesda's games into Action/Adventures.
"Well, Tomb Raider does that. We play a role when we are with Lara Croft. Therefore by your definition, Tomb Raider is an RPG."
And to this I say, no, Tomb Raider is not an RPG.

In any Elder Scrolls game, any table-game, and in some of the MMOs I've played, I was able to create my own character, but I was also able to do whatever I want with this character. Because doing what I want (or better yet, doing what the character wants) is the actual focus of the game. See? Not the quests, not the adventures.
I can make a character who goes picking flowers for instance (and I have!). All she does is pick flowers all day, that is what she wants to do, and best of all, the game supports this.

With Tomb Raider, sure, Lara Croft can go around looking at flowers and maybe go for a swim, however this is not what playing the game is really about. To play the game means to do the adventures. Solve the puzzles. Find the secrets. Otherwise, all there is left is standing around, crouching, shooting into thin air. Doing flips in mid-air.
But then there are JRPGs, in which most of them are considered roleplaying games by the general gaming public, yet their stories are very fixated and often linear. Though there are also some which offer lots of choices along the way, too. But I can't remember playing a JRPG in which I was allowed to create whomever I wanted. I really don't know. I will leave that one open. I've played some Final Fantasy, some Legends of Dragoon, etc. but I haven't really thought much about why they'd be considered RPGs, or not.
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Gosh, I apologize for writing that novel.
