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Flash cards have been suggested as a possible replacement for the floppy disk, but this has not happened, largely because of the lack of standardisation in the flash memory card market. USB Keydrives, which work on almost any computer with a USB port, are filling this role instead.
| Name | Acronym | Form factor |
|---|---|---|
| CompactFlash I | CF-I | 43 × 36 × 3.3mm |
| CompactFlash II | CF-II | 43 × 36 × 5.5mm |
| SmartMedia Card | SMC | 45 × 37 × 0.76mm |
| Memory Stick | MS | 50.0 × 21.5 × 2.8mm |
| Multi Media CardMB Multi Media Card Multi Media Card (MMC is a solid state disk or flash memory data storage device. It is based on Toshiba's NAND-based flash memory, and is therefore much smaller than earlier systems based on Intel NOR-based memory such as Compact Flash | MMC | 32 × 24 × 1.5mm |
| Secure Digital CardSecure Digital or SD is a flash memory data storage device based on Toshiba's earlier Multi Media Cards (MMC). SD is slightly thicker, and includes features that allow the secure exchange of data, enabling usage restrictions to placate copyright holders. | SD | 32 × 24 × 2.1mm |
| miniSD CardAnnounced for the first time by at CeBIT 2003, the miniSD joined the MemoryStick Duo and XD card at this small form factor. The miniSD card was adopted in 2003 by the as an ultra-small form factor extension to the SD card standard. While the new cards wer | miniSD | 21.5 × 20 × 1.4mm |
| xD-Picture CardxD-Picture Card is a format of flash memory data storage device developed and introduced to the market in July 2002 by Olympus and Fujifilm, and manufactured by the Toshiba Corporation. xD cards are designed for the digital photography market, and are an | xD | 20 × 25 × 1.7mm |
Since all sorts of EEPROM devices only allow a finite number of write cycles, some of these cards incorporate wear levellingWear levelling is a technique used by EEPROM ('flash') computer memory systems in order to spread wear caused by repeated writing evenly across a chip, and thus avoid wearing out specific sections of the chip. This wear effect is due to the fact that EEPR algorithms to spread the wear and to avoid wearing out specific places which are often written to.
See also: keydrive.
Computer storage media DigitalA digital system is one that uses discrete values rather than a continuous spectrum of values: compare analog. The word comes from the same source as the word digit: the Latin word for finger (counting on the fingers) as these are used for discrete counti Cameras