Play-by-Email
With the rise of the Internet, email and websites have largely replaced postal gaming and postal games zines. Play by mail games differ from popular online multiplayer games in that, for most computerized multiplayer games, the players have to be online at the same time - also known as synchronous play. With a play by mail game, the players can play whenever they choose, since responses need not be immediate; this is sometimes referred to as turn-based gaming and is common among browser-based games. Some video games can be played in turn-based mode: one makes one's "move", then play for that player stops, and the turn passes to another player who to makes his or her move in response.
Several non-commercial email games played on the Internet and BITNET predate these.
Some cards games like poker can also be played by Email using cryptography (see for example a patent application from FXTOP, another algorithm exists in Applied Cryptography from Bruce Schneier in case of 2 players°
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