This is an analog mass flow controller calibration calculator originally written for Tylan General / Process Management Technologies in Austin TX in 1994 after I graduated from ITT Tech and on my first job. Mass flow controllers were used to regulate the volume of different gases exposed to wafers during the manufacturing process. They were analog with the first digital devices just then arriving.
I went into enterprise system administration and then on to cyber security today. Now that we are bringing semiconductor manufacturing back 'home', let me know if I need to port this to Golang. :-))
tl;dr My first program written in basic and ran on MS DOS via x486 computer