A role-playing game (RPG) is a type of game where players assume the roles of imaginary characters in a scenario created by the game developer and vicariously experience the adventures of these characters.
In role-playing games players often team up to generate narratives. The play progresses according to a preset scheme of rules and strategy, within which players may invent liberally. Player options shape the course and conclusion of role-playing games.
Role-playing games are usually more gung-ho and casual fun than competitive. A role-playing game unites its participants into a single team that fights as a group. A role-playing game rarely has winners or losers. This makes role-playing games uniquely different from board games, card games, sports and other types of games. Role-playing games attract because they fire the players' imagination.
There are many different types of role-playing games. The PC-based RPG-s of today aren't an original genre; they are derived from board-based or real-life games that have been popular with children and even grown-ups for a long, long time. One such RPG might involve guests at a dinner party acting out suspects in a murder mystery, while another might involve players sitting around a bonfire and narrating parts of a story and rolling dice. Another RPG might consist of costumed participants recreating a medieval battle with padded armor and heavy weapons.
At their nucleus, role-playing games are a form of interactive and mutual storytelling. Simple forms of role-playing exist in traditional children's games such as "cops and robbers," "dogs and mailmen," "cowboys and Indians," and "playing house" or doctor.
The original form of role-playing game was the fantasy war game, inspired by brave knight and witchcraft lore and using minute figures and scale terrain grids to demonstrate action in a way similar to that of strategic war games.
Role-playing games have rules known usually as game mechanics. Almost all role-playing games require the participation of a game master (GM), who narrates the game session and acts as the moderator and rules arbitrator. The rest of the participants create and play inhabitants of the game setting, known as player characters (PCs). The player characters collectively are known as a "party".
Internet role-playing games range from graphical games such as EverQuest to simple text based games. They can also be divided into genres by the imaginary locale where they take place. Fantasy RPGs draw their inspiration from fantasy literature, such as the works of J. R. R. Tolkien. The best games in this field are Dungeons & Dragons, Exalted, Palladium Fantasy, RuneQuest, Legend of the Five Rings etc.
Science fiction RPGs are inspired by science fiction literature. The setting is generally in the future. The popular games are Rifts, Traveller, Cyberpunk 2020, Paranoia, Shadowrun and so forth.
Horror RPGs are inspired by horror literature. Horror RPGs can be divided into two groups. The first is inspired by the works of H. P. Lovecraft, focusing on humanity's fight against malevolent, extra-dimensional entities. The second centres around playing supernatural creatures, such as vampires, changelings, and werewolves. The top titles are Call of Cthulhu, Kult, World of Darkness Changeling: The Dreaming, Vampire: The Masquerade, Vampire: The Requiem, Werewolf: The Apocalypse, Werewolf: The Forsaken, Hunter: The Reckoning, Orpheus, and Mage: The Ascension.
Historical RPGs, as you can probably imagine, take place in the past. Settings that have been explored in role-playing games include Pendragon (based on Arthurian legends), Sengoku (about Japanese warring states), Recon (regarding the Vietnam War), Fantasy Imperium (takes place in historical Europe).
Superhero role-playing games are inspired by superhero comic books and graphic novels. The major games are Champions, DC Heroes, Marvel Super Heroes, Mutants and Masterminds.