BellLabs researcher. One of the InventorsOfUnix. Also wrote the troff typesetting program in 1973 for BellLabs' original PDP-11 UnixOperatingSystem - see http://www.troff.org/history.html and also TexLanguage. Full name Joseph F. Ossanna. Died in 1977.
Descended from programs that ran on CompatibleTimeSharingSystem and MulticsOs, Ossanna's troff was not only an early typesetting program but the first Unix application to pay the bills. (BellLabs financed PDP-11 Unix as a project to produce a working document-processing system for internal use, not as a research OS - see UnixHistory.) Versions of troff remained in common use for many years - the program is less sophisticated than TeX but also more lightweight.