A single loop occurs when a player takes a meaningful action, which does not require the action of another player to determine a win, does not occur in the same environment as other players and does not affect anyone else’s game. In simpler terms, this means games played alone. It also covers much of the play of social games and some of the more solitary quests of massive multiplayer games.
Single loops are asynchronous and atemporal. Play based on single loops is often described as single-player. Single-player gaming is perhaps the most important change that videogames brought to the art form of games. Rather than just simple puzzles or permutation games, single player videogames are entertaining activities, large simulations and epic stories. They are why the games industry is so successful.