cahos rahne veloza is correct, even if you play the role of a character, that doesn't mean it is a role playing game... according to the game's content, how can you say metal gear it's an rpg??... yes, okay, you do play the role of a character, but that alone will never ever do a rpg...this is an extract from wikipedia, http://en.wikipedia.org/wiki/Video_game_genres#Role-playing_games...[quote author=wikipedia ]
Role-playing games
Computer role-playing games (CRPGs or simply RPGs) draw their gameplay from traditional role-playing games like Dungeons & Dragons. Most cast the player in the role of one or more "adventurers" who specialize in specific skill sets (such as combat or casting magic spells) while progressing through a predetermined storyline. Many involve maneuvering these character(s) through an overworld, usually populated with monsters, that allows access to more important game locations, such as towns, dungeons, and castles.
Since the emergence of affordable home computers coincided with the popularity of paper and pencil role-playing games, this genre was one of the first in video games and continues to be popular today. Gameplay elements strongly associated with RPGs, such as statistical character development through the acquisition of experience points, have been widely adapted to other genres such as action-adventure games.
Though nearly all of the early entries in the genre were turn-based games, modern CRPGs have introduced a real-time aspect. Thus, the CRPG genre has followed the strategy game's trend of moving from turn-based to real-time combat. The move to real-time combat began with the release of Square Co.'s (now Square Enix) Final Fantasy IV, the first game to use the Active-Time Battle system; this was quickly followed by truly real-time games like Ultima VII.
There are two different types of RPGs. The first involves the player creating a character and a non-linear storyline along which the player makes his own decisions. In the second type the player controls a party of pre-made characters through a linear storyline. These styles are sometimes referred to as Western and Japanese Role-Playing Games respectively, although there are numerous exceptions.
Action role-playing
The action role-playing game or Action RPG is a type of computer and console role-playing game which incorporates elements from action games or action-adventure games. So-called "Diablo clones" are also part of this genre.
Although the precise definition of the genre varies, the typical action RPG features a heavy emphasis on combat, often simplifying or removing non-combat attributes and statistics and the effect they have on the character's development.[1] Additionally, combat always takes place using a real-time system (hence the "action") that relies on the player's ability to perform particular actions with speed and accuracy to determine success, rather than mainly using the player character's attributes to determine this.
Tactical role-playing
The tactical role-playing game sub-genre principally refers to strategy-derived games as an alternative to the traditional RPG system. In such titles, the system has been tailored to incorporate gameplay from strategy games. The genre has its origins in tabletop role-playing games, where each player has time to decide his or her character's action. The term "tactics" was not widely used to describe such titles until Final Fantasy Tactics was released, where it popularized the genre in North America, although games such as Shining Force were part of the genre years beforehand.
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