Floppy Disk Drives / Floppy Disks Floppy disk drives were originally introduced commercially as a read-only device in the early 1970s. These early floppy disk drives were used to hold microcode and diagnostics for large IBM mainframe computer systems. These disk drives were using 8-inch floppy diskettes recorded on only one side. By changing these diskettes inside the floppy drive, technicians could easily update the microcode to the latest revisions or load diagnostics easily. The storage capacity of these early readonly drives was less than 100 kilobytes. In 1973 a new upgraded 8 inch drive with read/write capability and a capacity of about 250 kilobytes began shipping which IBM used in data entry systems. This drive incorporated many technical improvements and became a model for drives still in use today. As time went on, designers learned how to reliably record on both sides of the diskette as well as increase the density of the data recorded on the diskette. Modern floppy drives ...