This became a standard platter size and drive form-factor for many years, used also by other manufacturers. In 1962, IBM introduced its model 1311 disk, which used six 14-inch (nominal size) platters in a removable pack and was roughly the size of a washing machine. IBM's first hard drive, the IBM 350, used a stack of fifty 24-inch platters and was of a size comparable to two large refrigerators. List Past and present HDD form factorsĪ newer 2.5-inch (63.5 mm) 6,495 MB HDD compared to an older 5.25-inch full-height 110 MB HDD Drives may slot into a drive bay of the corresponding size.Ĭompared to flash drives in same form factor, maximum rotating disk drive capacity is much smaller, with 100 TB available in 2018, and 32 TB for 2.5-inch. Standardized form factors and interface allow a variety of peripherals and upgrades thereto with no impact to the physical size of a computer system. Since the invention of the floppy disk drive, various standardized form factors have been used in computing systems.
