You are killing me here — I remember all that stuff.
I started working at GTE Data Services in 1977 as a computer operator. We had Honeywell DPS 66/60 mainframes that filled an entire room. The ‘hard drives’ were as big as washing machines and had what looked like large LPs stacked on top of each other. Data could also be stored on tapes, paper tapes or card decks.
This was considered the “time-sharing” part of the business. GTE Telephone Operations employees could log into the mainframe via a ‘dumb’ terminal (3270) and a dial-up modem at 300 baud. When they went to 1200 baud everyone thought that it was the best. Thirty-second response time was considered good. This was WAY before anyone ever heard of a PC. Now there is more computing power in a credit card sized calculator than one mainframe tower.