It is generally accepted that "Role Playing" is an important aspect of playing a "Role Playing Game" but there is little consensus as to what this means. Some people insist upon an interpretation which places Role Playing in the mould of Thespian and Psychotherapy roleplay. Some people go further and say that since D&D didn't contain rules or recommendations for anything like this, nor did it originally call itself a Role Playing Game, that D&D was not a Role Playing Game. Derogatory terms such as "Rollplayer" are used for people who do not toe the line as regards the correct sort of role playing. On the other hand, some people say that Story Games are not RPGs, despite containing role playing.
Why did people call D&D a Role Playing Game?
It is true that in the earliest days, D&D didn't call itself a Role Playing Game – it was "Rules for Fantastic Medieval Wargames Campaigns Playable with Paper and Pencil and Miniature Figures". However it does mention role playing, that is – literally – playing a role:
"Before they begin, players must decide what role they will play in the campaign, human or otherwise, fighter, cleric, or magic-user."So how did this "playing a role" morph into "role playing", and what is meant by it?
I don’t believe that people referred to D&D as a "role playing game" implying an adherence to the Thespian and Therapy meaning of roleplay – to understand what they meant you should discard all prior baggage associated with the term and instead look at the game that they are trying to describe with the term.
In D&D, role playing, or playing the role of your character, simply means you are told by the DM what your character sees / hears / experiences, you ask questions about this information and say what your character does, and the rules are used to resolve situations.
It is not an understatement to say that this was an entirely new concept in games. It does not require you to identify with your character, pretend to be your character, or to think as your character (though you may choose to do so). It is entirely compatible with Thespian/Therapy roleplay; but how much you incorporate this into your games is a matter of personal taste.
Is this a helpful or meaningful definition of "Role Playing"?
In this form of Role Playing, you cannot find out things which your character does not know, you are not told about things your character does not experience, you have no influence over events other than that which your character can exert. That is, Role Playing is both an enabler (you have complete control over the character's decisions) and a restriction (you cannot do more than play your character's role).
This definition allows you to clearly see how come some adherents of "Role Playing Games" insist that Character Choice is all important, Causation* is imperative, Cut Scenes are an irrelevant distraction, Thespianism** is optional, and the degree of Simulation is a matter of taste.
It is also clear that you can easily roleplay without it being an RPG (e.g. dress up and talk in character when playing Cluedo) and also that by removing the restriction on your actions to be limited to the role of your character (e.g. collaborative story telling games) you break something fundamental to RPGs to the point that it is at the least misleading for it to be referred to as an RPG.
Strict Role Playing
To this end, I suggest that we refer to this influence-and-knowledge-remains-within-the-role-of-the-character which characterises D&D (and most other RPGs) as "Strict Role Playing" to distinguish this play from other uses of the term and to highlight the difference. It is then possible to talk about the difference between strict RPG play and other forms of RPG (such as Story Games) without annoying adherents of other approaches by saying they aren't roleplaying and hence (by inference) aren't "doing it properly", and hence allowing people to discuss the issues and understand other viewpoints.
* By Causation I mean what people often term associated mechanics. Players say what their character does, and the game resolves the character's actions.
** By Thespianism, I mean putting on a voice or affecting mannerisms or style of speech, ever asking yourself "what is my Character's motive in this scene?", or taking actions based upon the beliefs of your character rather than what is optimal. I do a bit of all of this when I play RPGs!