QWK (file Format)
QWK is file-based offline mail reader format that was popular among bulletin board system (BBS) users, especially users of FidoNet and other networks that generated large volumes of mail. QWK was originally developed by Mark "Sparky" Herring in 1987 for systems running the popular PCBoard bulletin board system, but it was later adapted for other platforms. During the height of bulletin board system popularity, several dozen offline mail readers supported the QWK format.
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