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DATA STORAGE DEVICES A data storage device is a device for recording (storing)information (data). A storage device may hold information, process information, or both. A device that only holds information is a recording medium. EXAMPLES: 1. Multimedia Card A flash memory card that provides storage for cellphones, PDAs and other handheld devices. Introduced in 1997 with a 4MB capacity, the 32x24x1.4mm card weighs less than two grams. By 2005, storage increased to 2GB. The card uses flash memory for read/write applications or ROM chips (ROM-MMC) for static information, the latter widely used for adding applications to a Palm PDA. 2. MultiMediaCards and SD Memory Cards share the same footprint, but MMCs are thinner and have only seven pins compared to nine. MMC cards can be read in SD Card readers, but SD Cards cannot be read in readers designed for MMC only. Typically, an MMC is used as storage media for a portable device, in a form that can easily be removed for access by a PC. 3. USB Drive Also known as a "flash drive," "pen drive," "keychain drive," "key drive," "USB key," "USB stick" and "memory key," numerous brand names have also been coined such as Lexar's JumpDrive and Trek 2000 International's ThumbDrive. A flash memory card that plugs into the computer's USB port. Small enough to hook onto a keychain, it emulates a small disk drive and allows data to be easily transferred from one machine to another. 4. XD Picture Card The xD-Picture Card is a type of flash memory card, used mainly in digital cameras. xD originally stood for extreme Digital. The cards were developed by Olympus and Fujifilm and introduced into the market in July 2002. 5. SD Memory Card Secure Digital (SD) is a flash (non-volatile) memory card format developed by Matsushita, SanDisk and Toshiba for use in portable devices, including digital cameras, handheld computers, PDAs and GPS units. 6. Bubble memory is a type of non- volatile computer memory that uses a thin film of a magnetic material to hold small magnetized areas, known as bubbles, which each store one bit of data. Bubble memory started out as a promising technology in the 1970s, but failed commercially as hard disk prices fell rapidly in the 1980s. 7. Optical disk, any of a variety of information storage disks that are played or read using a laser. Optical disks include compact discs (CDs and CD-ROMs), laser discs (see videodisc), and digital versatile discs (or digital video discs; DVDs and DVD-ROMs). In computing, sound reproduction, and video, an optical disc is a flat, circular, usually polycarbonate disc where data is stored in the form of pits (or bumps) within a flat surface, usually along a single spiral groove that covers the entire recorded surface of the disc. This data is generally accessed when a special material on the disc (often aluminium) is illuminated with a laser diode. 8. Floppy disk A floppy disk is a portable computer storage device that permits easy handling of data. Commonly used with personal computers, notebook computers, and word processors, such disks consist of flat, circular plates made of metal or plastic and coated with iron oxide. When a disk is inserted into the disk drive of a computer, information can be magnetically imprinted on this coating, which will thereafter permit easy location and retrieval of the same data. 9. Magnetic Tape A sequential storage medium used for data collection, backup and archiving. Like videotape, computer tape is made of flexible plastic with one side coated with a ferromagnetic material. Tapes were originally open reels, but were superseded by cartridges and cassettes of many sizes and shapes.
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