If your Pop splurged on the IBM PC, you had A:\ <AND> B:\, so you could load IBM DOS 1.0 (1.1?) in A:\ and didn't have to remove the disk to put in your Visicalc disk. Imagine, an OS that loaded in 640K of RAM. Oh, and programs that loaded from 360K disks. You didn't install programs to the hard drive back then, as there were no commercially available hard drives for home users. Yup, I is old.