Play-by-Internet

A play-by-post role-playing game game (or sim) is an online text-based role-playing game in which players interact with each other and a predefined environment via text. It is a subset of the online role-playing community which caters to both gamers and creative writers. Play-by-post games may be based on other role-playing games, non-game fiction including books, television and movies, or original settings. This activity is closely related to both interactive fiction and collaborative writing. Compared to other roleplaying game formats, this type tends to have the loosest rulesets.

Play-by-post roleplaying has its origins on the large computer networks and bulletin board systems of major universities in the United States in the 1980s, where it drew heavily upon the traditions of fanzines and off-line role-playing games. The introduction of IRC enabled users to engage in real-time chat-based role-playing and resulted in the establishment of open communities.

Development of forum hosting software and browser-based chat services such as AOL and Yahoo Chat increased the availability of these mediums to the public and improved accessibility to the general public. The popularity of play-by-post games peaked in the early 2000s with online chat services and free remotely hosted message boards such as invisionFree and ProBoards

Unlike other forms of online role-playing games such as MUDs or MMORPGs, the events in play-by-post games are rarely handled by software and instead rely on participants or moderators to make decisions or improvise. Players create their own characters and descriptions of events and their surroundings during play. Results of combat, which may include Player versus player encounters, may be determined by chance through dice rolls or software designed to provide a random result. The results of random chance may need to be provided to the players in order to avoid disputes that may be a result of cheating or favoritism. Alternatively a forum may be diceless and rely on cooperation between players to agree on outcomes of events and thus forgo the use of randomisers.

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Wikipedia