Play-by-web
An increasingly popular format for play-by-email games is play-by-web. As with play-by-email games the players are notified by email when it becomes their turn, but they must then return to the game's website to continue playing what is essentially a browser-based game. The main advantage of this is that the players can be presented with a graphical representation of the game and an interactive interface to guide them through their turn. Since the notifications only have to remind the players that it is their turn they can just as easily be sent via instant messaging.
Some sites have extended this gaming style by allowing the players to see each other's actions as they are made. This allows for real time playing while everyone is online and active, or slower progress if not.
Increasingly, this format is being adopted by social and mobile games, often described using the term "asynchronous multiplayer."
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