List of disk drive form factors

Since the invention of the floppy disk drive, various standardized form factors have been used in computing systems.

Standardized form factors and interface allow a variety of peripherals and upgrades thereto with no impact to the physical size of a computer system.

[citation needed] With increasing sales of microcomputers having built in floppy-disk drives (FDDs), HDDs that would fit to the FDD mountings became desirable.

This smaller form factor, first used in an HDD by Seagate in 1980, was the same size as full-height 5+1⁄4-inch-diameter (130 mm) FDD, 3.25-inches high.

Most desktop models of drives for optical 120 mm disks (DVD, CD) use the half height 5¼" dimension, but it fell out of fashion for HDDs.

This smaller form factor is similar to that used in an HDD by Rodime in 1983, which was the same size as the "half height" 3½" FDD, i.e., 1.63 inches high.

Seagate released a 7 mm drive aimed at entry level laptops and high end netbooks in December 2009.

Western Digital released on April 23, 2013 a hard drive 5 mm in height specifically aimed at Ultrabooks.

This form factor, originally introduced by Intégral Peripherals in 1991, evolved into the ATA-7 ZIF with dimensions as stated but with a total length of 71mm.

This form factor was introduced in 1999, as IBM's Microdrive to fit inside a CF Type II slot.

Toshiba announced this form factor in January 2004 for use in mobile phones and similar applications, including SD/MMC slot compatible HDDs optimized for video storage on 4G handsets.

By 2009, all manufacturers had discontinued the development of new products for the 1.3-inch, 1-inch and 0.85-inch form factors due to falling prices of flash memory, which has no moving parts.