History and Evolution of Floppy Disk Drives

Storage

 

History and Evolution of Floppy Disk Drives

8-Inch Floppy Disks

  • Invention and Development: Invented and made by IBM in the late 1960s.
  • Commercial Availability: Became commercially available in 1971.
  • Market Introduction: Sold separately starting in 1972 by Memorex and others.
  • Disk Diameter: 8 inches (203.2 mm).

5¼-Inch Floppy Disks

  • Introduction: Introduced by Shugart Associates in 1976.
  • Common Capacity: 360 KB (368,640 bytes) for the Double-Sided Double-Density (DSDD) format using MFM encoding in DOS-based PCs.
  • IBM’s Innovation: IBM introduced the 1.2 MB (1,228,800 bytes) dual-sided 5¼-inch floppy disk in 1984 with its PC/AT.
  • Popularity: The 1.2 MB format never became very popular.

3½-Inch Floppy Disks

  • Introduction by IBM: IBM started using the 720 KB double-density 3½-inch microfloppy disk in its Convertible laptop computer in 1986.
  • High-Density Version: The 1.44 MB high-density version was introduced with the IBM Personal System/2 (PS/2) line in 1987.
  • Extended-Density Format: In 1988, Y-E Data introduced a drive for 2.88 MB Double-Sided Extended-Density (DSED) diskettes.
  • IBM Usage: The 2.88 MB format was used in IBM’s top-of-the-line PS/2, some RS/6000 models, and the second-generation NeXTcube and NeXTstation.
  • Market Success: The 2.88 MB format had limited market success due to lack of standards and the movement towards 1.44 MB drives.