Similar story here - as a physics student, I used VMS in the first year of uni, mainly for its Fortran compiler (WATFOR) and the NAG libraries, and Unix thereaf

Similar story here - as a physics student, I used VMS in the first year of uni, mainly for its Fortran compiler (WATFOR) and the NAG libraries, and Unix thereafter. Both had advantages and disadvantages, VMS was touted as more secure (as in, security was a fundamental consideration in its design, whereas it wasn't the case for Unix). I particularly liked the automatic versioning of files, making reversion to earlier known-good files simple. VMS knowledge came in handy years later when I had to work in VMS Fortran on the company VAX - I even coded the VMS Fortran random number generator in g77 (thanks to the excellent documentation) for consistency when we ported our code to DOS after the VAX was shut down.