High Quality Content by WIKIPEDIA articles! The JAM Message Base Format was one of the most popular file formats of message bases on DOS-based BBSes in the 1990s. JAM stands for "Joaquim-Andrew-Mats" after the original authors of the API, Joaquim Homrighausen, Andrew Milner, Mats Birch, and Mats Wallin. Joaquim was the author of FrontDoor, a DOS-based FidoNet-compatible mailer. Andrew was the author of RemoteAccess, a popular DOS-based Bulletin Board System. JAM was originally released in 1993 in C, however the most popular implementation was Mark May`s "MK Source for Msg Access" written in Pascal which also saw its initial release in 1993.