1971, Science and Technology: First 8-inch Floppy Disk by IBM

In 1967, IBM began developing a drive that led to the creation of the world’s first floppy disk (diskette) and disk drive. It was commercially introduced in 1971 in an 8-inch (20 cm) read-only format. The inspiration came from the flexible magnetic disk used by Telefunken in its "Plattendiktiergerät Traveller" from 1959.

Left to right: 8-inch, 5.25-inch and 3.5-inch floppy disk

A diskette is divided into tracks (radially) and sectors (angularly), whereas the Telefunken disk featured gramophone-like grooves. The first read-write floppy disk drive was the Memorex 650, introduced in 1972. Various storage capacities were available in the early years due to a lack of standardisation, a situation that persisted until the later years of the third generation (3.5-inch) floppy disks.

Telefunken "Plattendiktiergerät Traveller" 1959

Telefunken "Plattendiktiergerät Traveller" disc 1959

Properties of he IBM standard format

• disk diameter 20 cm (8-inch).
• SD (single density) with 250 kbit/s data rate or / DD (double density) with 500 kbit/s data rate
• 360 rpm (revolutions per minute)
• 26 sectors/track; 73 data tracks, 1 index track, 2 spare tracks, 1 reserved track
• 128 bytes/sector
• total disk capacity 3203128 bits (242944 bytes of data with this format)

Left to right: 8-inch, 5.25-inch and 3.5-inch floppy disk drives

Trivia

• In late 1976, the 5.25-inch floppy disk and disk drive were introduced to the market by Shugart Associates.
• The first 3.5-inch diskette was introduced by Sony in 1981.