FileWare floppy disk drives and diskettes were designed by Apple Computer as a higher-performance alternative to the Disk II and Disk III floppy systems used on the Apple II and Apple III personal computers. The drive is named Apple 871 in service documentation, based on its approximate formatted storage capacity in kilobytes, but is most commonly known by their codename Twiggy, after the famously thin 1960s fashion model named Twiggy.

The Disk II Floppy Disk Subsystem, often rendered as Disk ][, is a 5 +1⁄4-inch floppy disk drive designed by Steve Wozniak at the recommendation of Mike Markkula, and manufactured by Apple Computer, Inc. It went on sale in June 1978 at a retail price of US$495 for pre-order; it was later sold for $595 including the controller card and cable. The Disk II was designed specifically for use with the Apple II personal computer family to replace the slower cassette tape storage.