History of the floppy disk
Floppy disks were a universal data format from the 1970s into the 1990s.
A floppy disk is a data storage device consisting of a thin, flexible magnetic disk inside a rectangular plastic casing. It is accessed through a floppy disk drive (FDD). From the 1970s through the 1990s, floppy disks were a nearly universal way to store primary data, create backups, and transfer files between computers.
Development began in 1967 at an IBM facility in San Jose, California, resulting in the first floppy disk and drive. The 8-inch format hit the market in 1971. The more convenient 5¼-inch disk arrived in 1976, becoming standard on word processors and personal computers. It was gradually replaced by the 3½-inch format, introduced in 1982, though both coexisted for a long time. The stated sizes are nominal; actual cartridge dimensions are 130 mm and 90 mm, with the disks themselves slightly smaller. Other sizes appeared over the years but saw limited success.
Floppy disks remained popular for nearly four decades, but usage dropped sharply in the mid-to-late 1990s. After 2000, they became rare, mainly used with older hardware, especially legacy industrial and musical equipment. Sony produced its last new floppy disks in 2011.
IBM’s late-1960s plan to use RAM as a writable control store for future systems created a need for a cheap, reliable read-only device to store and load microprograms. The goal was a read-only drive under $200 and media under $5. Alan Shugart, IBM San Jose’s Direct Access Storage Product manager, assigned the task to David L. Noble, who tried developing a new tape but failed. The project then went to Donald L. Wartner, Herbert E. Thompson, and engineers Warren L. Dalziel, Jay Brent Nilson, and Ralph Flores. They created the IBM 23FD Floppy Disk Drive System (codenamed Minnow), an 8-inch read-only flexible diskette called the “memory disk” holding 80 kilobytes. Initially bare, the disk was placed in a fabric-lined plastic envelope to combat dirt. The floppy disk drive patent (#3,678,481) was issued July 18, 1972, to Dalziel, Nilson, and Wartner. IBM launched the diskette commercially in 1971.
The 23FD first shipped in 1971 as the control store loader for the 2835 Storage Control Unit, later becoming standard in most System 370 units and other IBM products. Internally, IBM used another device, codenamed Mackerel, to write floppy disks for field distribution.
- First introduced
- 1971 (8-inch format)
- 5¼-inch introduced
- 1976
- 3½-inch introduced
- 1982
- Last new floppy disks manufactured
- 2011 (by Sony)
- Initial 8-inch capacity
- 80 kilobytes (read-only)
- First read/write 8-inch capacity
- 175 kB (Memorex 650, 1972)
- Peak 8-inch capacity
- 1–1.2 MB (Double Sided Double Density, 1977)
Lore & Background
In 1967, at an IBM facility in San Jose, California, work began on a drive that led to the world's first floppy disk and disk drive. It was introduced into the market in an 8-inch format in 1971. The disk was initially read-only, holding 80 kilobytes of data, and was enclosed in a plastic envelope lined with fabric to remove dust. The Floppy Disk Drive Patent #3,678,481 was issued July 18, 1972 with named inventors Warren L. Dalziel, Jay B. Nilson, and Donald L. Wartner. IBM introduced the diskette commercially in 1971, first shipping as the 23FD, the control store load device of the 2835 Storage Control Unit.
Other suppliers recognized the opportunity for a read/write FDD. Shugart, by then at Memorex, shipped the Memorex 650 in 1972, the first commercially available read-write floppy disk drive, with a data capacity of 175 kB. IBM's first read/write FDD, the 33FD code named 'IGAR,' first shipped in May 1973 as a component of the 3740 Data Entry System. The medium sold separately as 'Diskette 1' and used a soft sector recording format storing nearly 250 kB. In 1973, Shugart founded Shugart Associates, which became the dominant manufacturer of 8-inch floppy disk drives; its SA800 became the industry standard for form factor and interface.
The more conveniently sized 5¼-inch disks were introduced in 1976, following a meeting where An Wang of Wang Laboratories informed Shugart Associates that the 8-inch format was too large and expensive for desktop word processing machines. The new drive stored 98.5 kB, later increased to 110 kB. Shugart's initial 5¼-inch drive was the 35-track, single-sided SA-400, which introduced the 34-pin interface that became an industry standard. By 1978 ten different manufacturers were producing 5¼-inch drives. The 3½-inch format was first introduced in 1982, and there was a significant period where both 5¼-inch and 3½-inch formats were popular.
Reader's Guide
Floppy disks remained a popular medium for nearly 40 years, but their use was declining by the mid- to late 1990s. After 2000, floppy disks were increasingly rare and used primarily with older hardware, especially with legacy industrial and musical equipment. Sony manufactured its last new floppy disks in 2011. The 8-inch floppy found a place as one of the few 'high speed, mass storage' devices affordable to individuals and small businesses when the first microcomputers were being developed in the 1970s, though drives were still expensive, typically costing more than the computer they were attached to. The first microcomputer operating system, CP/M, originally shipped on 8-inch disks. The 5¼-inch drive was considerably less expensive and started appearing on CP/M machines. At the end of 1978 the typical floppy disk price per piece was $5 to $8, and sales for all types of drives and media were expected to reach $135 million for media and $875 million for drives. The 5¼-inch format was almost universal on dedicated word processing systems and personal computers, and was more slowly replaced by the 3½-inch format.
Did You Know?
- The first floppy disk was read-only, holding 80 kilobytes of data, and was initially bare before being enclosed in a fabric-lined plastic envelope to combat dirt.
- The Memorex 650, shipped in 1972, was the first commercially available read-write floppy disk drive, with a capacity of 175 kB.
- The 5¼-inch format was proposed after An Wang of Wang Laboratories told Shugart Associates that the 8-inch format was too large and expensive for desktop word processing machines.
Frequently Asked Questions
Who invented the floppy disk and where did it originate?
Development of the floppy disk began in 1967 at an IBM facility in San Jose, California, producing both the first disk and its drive. The resulting 8-inch format reached the commercial market in 1971.
What were the three main floppy disk sizes and when did each appear?
The original 8-inch disk debuted in 1971, followed by the more portable 5¼-inch in 1976 and the compact 3½-inch in 1982. Each smaller generation became the new standard on word processors and personal computers as it replaced the last.
When were the last new floppy disks actually manufactured?
Sony produced the final batch of new floppy disks in 2011, ending more than four decades of continuous production. By then, USB flash drives and optical media had long since overtaken floppies for everyday use.
How much data could the very first floppy disk hold?
The initial 1971 8-inch disk was read-only and stored a mere 80 kilobytes. The first read/write version, the Memorex 650 released in 1972, pushed capacity up to 175 kilobytes.
Why is the floppy disk considered a landmark in computing history?
From the 1970s through the 1990s, floppy disks served as the nearly universal medium for storing primary data, creating backups, and transferring files between machines. They bridged the transition from mainframe-era storage to the personal computer era.
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