Try VisiCalc, The very first spreadsheet. SuperCalc was the one bundled with the Osborne 1 PC using C/PM which was later ported to MSDOS. SuperCalc was the PC version of VisiCalc.
M class flares are not particularly strong, unless they are long duration. There were impulsive so they were not that strong. What makes them noteworthy is the length of time the solar activity has been near to the C floor! The solar flares needed to have blasted CMEs too so that 3 to 4 days later, there would be geomagnetic effects which would trigger auroras.