Scribe
Scribe was a markup language developed by Brian Reid, then a graduate student at Carnegie Mellon University, around 1980, along with the "Runoff" program that processed it into a printable document tailored to the particular user-selected output device. Its concept of separating structure from presentation was pioneering, and has been replicated in many markup languages, word processors, and other sytems since. Original manuscripts were created in any text editor (and often had the .MSS extension) using plain text with embedded markup commands which started with the @ sign. The output of Runoff was a file in whatever native format might be needed to control a printer or terminal, with control or escape sequences specific to that device which executed the desired effects indicated by the markup (e.g., boldface, font changes, etc.).
Scribe was the subject of some intellectual-property disputes after Reid began to commercialize it. The university claimed to own rights to the program since it was developed there (though by a student, not by faculty or staff), but they ultimately settled out of court and left the rights with the creator. There was also some criticism of the software publisher of the commercial version for embedding a "time bomb" that deactivated the program if a license fee was not paid within 90 days, which was denounced by free software activist Richard Stallman.