FORTRAN is a computer programming language similar to any other, except that it's focused primarily on number crunching. My Mom used fortran way back in the 1960s doing work on Lockheed satellite programs, and when she got back into the industry 20 years later, she was using updated versions of fortran working on fluid dynamics simulations. I think she still uses it occasionally.
As for whether it was actually used, it would not surprise me if it was in fact used. Fortran used to be common on "big iron", and being ported to small PCs was a significant step towards bringing small computers into wide use in the engineering and simulation business. By "simulation" I don't mean games, I mean hard-core fluid dynamics and systems simulation which is a completely different and highly computer-intensive field.
It's very structured, and even the code formatting such as indentation from the left margin means something. Fortran was the first high level programming language I learned in high school, but I haven't used it since then.
I doubt it will be any use to you, and if it's a proprietary version they used to keep track of then they might appreciate it's return, but since it's so old they probably wrote it off long ago.
