PBEM

From Wikipedia

Play-by-mail games, sometimes known as "Play-by-post", are games, of any type, played through postal mail or e-mail. One example, chess, has been played by mail for centuries (when played in this way, it is known as correspondence chess). Another example, Diplomacy, has been played by mail since the 1960s, starting with a printed newsletter (a fanzine) written by John Boardman. More complex games, moderated entirely or partially by computer programs, were pioneered by Rick Loomis of Flying Buffalo in 1970. The first such game offered via email through a major online service was Quantum Space from Stormfront Studios, which debuted on AOL in 1989.

Play by mail games are often referred to as PBM games, and play by email is sometimes abbreviated PBeM -- as opposed to face to face (FTF) or over the board ( OTB ) games which are played in person. Another variation on the name is Play-by-Internet (PBI) or play-by-web (PBW). In all of these examples, player instructions can be either executed by a human moderator, a computer program, or a combination of the two.