FLOPPY DISK

 floppy disk, also called a diskette, is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles. Floppy disks are read and written by a floppy disk drive (FDD).

Floppy disks, initially as 8-inch (200 mm) media and later in 5¼-inch (133 mm) and 3½-inch (90 mm) sizes, were a ubiquitous form of data storage and exchange from the mid-1970 s well into the 2000 s.

By 2010, computer motherboards were rarely manufactured with floppy drive support; 3½-inch floppy disks can be used with an external USB floppy disk drive, but USB drives for 5¼-inch, 8-inch and non-standard diskettes are rare or non-existent, and those formats must usually be handled by old equipment.

While floppy disk drives still have some limited uses, especially with legacy industrial computer equipment, they have been superseded by data storage methods with much greater capacity, such as USB flash drives, portable external hard disk drives, optical discs, memory cards and computer networks.

History

History of the floppy disk

The earliest floppy disks, developed in the late 1960s, were 8 inches (200 mm) in diameter. they became commercially available in 1971. These disks and associated drives were produced and improved upon by IBM and other companies such as Memorex, Shugart Associates, and Burroughs Corporation. The phrase "floppy disk" appeared in print as early as 1970,^[4] and although in 1973 IBM announced its first media as "Type 1 Diskette" the industry continued to use the terms "floppy disk" or "floppy".

In 1976, Shugart Associates introduced the first 5¼-inch FDD. By 1978 there were more than 10 manufacturers producing such FDDs. There were competing floppy disk formats, with hard and soft sector versions and encoding schemes such as FM,MFM and GCR. The 5¼-inch format displaced the 8-inch one for most applications, and the hard-sectored disk format disappeared. In 1984, IBM introduced the 1.2 MB dual-sided floppy disk along with its AT model. IBM started using the 720 KB double-density 3½-inch microfloppy disk on its Convertible laptop computer in 1986 and the 1.44 MB high-density version with the PS/2 line in 1987. These disk drives could be added to older PC models. In 1988 IBM introduced a drive for 2.88 MB "DSED" diskettes in its top-of-the-line PS/2 models, but this was a commercial failure.

Throughout the early 1980s, limitations of the 5¼-inch format became clear. Originally designed to be more practical than the 8-inch format, it was itself too large; as the quality of recording media grew, data could be stored in a smaller area. A number of solutions were developed, with drives at 2, 2½, 3 and 3½ inches (and Sony's 90.0 mm × 94.0 mm disk) offered by various companies. They all shared a number of advantages over the old format, including a rigid case with a sliding metal cover over the head slot, which helped protect the delicate magnetic medium from dust and damage, and a sliding write protection tab, which was far more practical than the adhesive tabs used with earlier disks. The large market share of the 5¼-inch format made it difficult for these new formats to gain significant market share. A variant on the Sony design, introduced in 1982 by a large number of manufacturers, was then rapidly adopted; by 1988 the 3½-inch was outselling the 5¼-inch.

By the end of the 1980s, the 5¼-inch disks had been superseded by the 3½-inch disks. By the mid-1990s, the 5¼-inch drives had virtually disappeared, as the 3½-inch disk became the predominant floppy disk. The advantages of the 3½-inch disk were its smaller size and its plastic case, which provided better protection from dirt and other environmental risks, while the 5¼-inch disk was available cheaper per piece throughout its history, usually with a price in the range of 1/3 to 2/3 of a 3½-inch disk

Ubiquity

Floppy disks became ubiquitous in the 1980s and 1990s in their use with personal computers to distribute software, transfer data, and create backups. Before hard disks became affordable, floppy disks were often used to store a computer'soperating system (OS). Most home computers had a primary OS and BASIC stored as ROM, with the option of loading a more advanced disk operating system from a floppy disk. By the early 1990s, the increasing software size meant large packages like Windows or Adobe Photoshop required a dozen disks or more. In 1996, there were an estimated five billion floppy disks in use.Then, distribution of larger packages was gradually replaced by CD-ROM and online distribution (for smaller programs). An attempt to continue the floppy disk was the Super Disk in the late 1990s, with a capacity of 120 MB                                                                  and backward-compatible with standard 3½-inch floppies; a format war briefly occurred between SuperDisk and other high-density removable disc products, although ultimately flash memory, recordable CDs/DVDs, and online storage would render the matter irrelevant. External USB-based floppy disk drives are still available; many modern systems provide firmware support for booting from such drives.

Decline

Mechanically incompatible higher-density disks were introduced, like the Iomega Zip disk. Adoption was limited by the competition between proprietary formats and the need to buy expensive drives for computers where the disks would be used. In some cases, failure in market penetration was exacerbated by release of higher-capacity versions of the drive and media not backward-compatible with the original drives, dividing the users between new and old adopters. A chicken or the eggscenario ensued, with consumers wary of making costly investments into unproven and rapidly changing technologies, resulting in none of the technologies becoming an established standard.

Apple introduced the iMac in 1998 with a CD-ROM drive but no floppy drive; this made USB-connected floppy drives popular accessories, as the iMac came without any writable removable media device. This transition from standard floppies was relatively easy for Apple, since all Macintosh models originally designed to use a CD-ROM drive could boot and install their operating system from CD-ROM early on.

Recordable CDs with even greater capacity, compatible with existing infrastructure of CD-ROM drives, made the new floppy technologies obsolete. The floppy disk's remaining reusability advantage was then eliminated by re-writeable CDs. Networking, advancements in flash-based devices and widespread adoption of USB provided another alternative that in turn made both floppy disks and optical storage obsolete for some purposes. The rise of file sharing and multi-megapixel digital photography encouraged the use of files larger than most 3½-inch disks could hold. Floppy disks were commonly used as sneak ernet carriers for file transfer, but the broad availability of LANs and fast Internet connections provided a simpler and faster method of transferring such files. Other removable storage devices have advantages in both capacity and performance when network connections are unavailable or when networks a