Friday, May 23, 2025

IBM Disk Drives

User RTC on en.wikipedia, Public domain, via Wikimedia Commons

In the foreground, two IBM 350 disk drives, each with a capacity of 3.75 MB and consisting of a stack of fifty two, 24 inch disks. Production began in 1957. It wouldn't be possible to store even one photo from a smartphone on such a drive and the capacity is a little over 2.5 times the storage space of the 3 1/2" floppy disks that became available in the late 1980s. Those disks replaced the earlier, lower capacity 5 1/4" disks. (I used 8" floppy disks on a microprocessor development system. This was the first format of portable floppy and became commercially available in 1971).