External storage
In computing, external storage comprises devices that temporarily store information for transporting[citation needed] from computer to computer. Such devices are not permanently fixed inside a computer. Types of external storage devices include: punched cards
A punched card, punch card, IBM card, or Hollerith card is a piece of stiff paper that contains digital information represented by the presence or absence of holes in predefined positions. Now an obsolete recording medium, punched cards were widely used throughout the 19th century for controlling textile looms and in the late 19th and early 20th century for operating fairground organs and related instruments. They were used through the 20th century in unit record machines for input, processing, and data storage. Early digital computers used punched cards, often prepared using keypunch machines, as the primary medium for input of both computer programs and data. Some voting machines use punched cards.
cassette tapes The Compact Cassette, often referred to as audio cassette, cassette tape, cassette, or simply tape, is a magnetic tape sound recording format. Although designed originally for dictation, improvements in fidelity led the Compact Cassette to supplant the Stereo 8-track cartridge and reel-to-reel tape recording in most non-professional applications.[1] Its uses ranged from portable audio to home recording to data storage for early microcomputers. Between the early 1970s and the late 1990s, the cassette was one of the two most common formats for prerecorded music, first alongside the LP record and later the Compact Disc.[2]Compact Cassettes consist of two miniature spools, between which a magnetically coated plastic tape is passed and wound. These spools and their attendant parts are held inside a protective plastic shell. Two stereo pairs of tracks (four total) or two monaural analog audio tracks are available on the tape; one stereo pair or one monophonic track is played or recorded when the tape is moving in one direction and the second pair when moving in the other direction. This reversal is achieved either by manually flipping the cassette or by having the machine itself change the direction of tape movement ("auto-reverse").[3]
floppy disks A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles. They are read and written by a floppy disk drive (FDD).Invented by IBM, floppy disks in 3.5-inch (89 mm), 5.25-inch (133 mm) and 8-inch (200 mm) forms were an ubiquitous form of data storage and exchange from the mid-1970s to the 2000s.[1]While floppy disk drives still have some limited uses, especially with legacy industrial computer equipment, they have been
superseded by data storage methods with much greater capacity, such as USB flash drives, portable external hard disk drives, optical discs, memory cards, and computer networks.
Zip disks The Zip drive is a medium-capacity removable disk storage system that was introduced by Iomega in late 1994. Originally, Zip disks launched with capacities of 100 MB, but later versions increased this to first 250 MB and then 750 MB.The format became the most popular of the super-floppy type products which filled a niche in the late 1990s portable storage market. However it was never popular enough to replace the 3.5-inch floppy disk nor could ever match the storage size available on rewritable CDs and later rewritable DVDs. USB flash drives ultimately proved to be the better rewritable storage medium among the general public due to common availability of USB ports built into most models of personal computer. Zip drives fell out of favor for mass portable storage during the early 2000s. The Zip brand later covered internal and external CD writers known as Zip-650 or Zip-CD, which had no relation to the Zip drive.
CDs The Compact Disc (also known as a CD) is an optical disc used to store digital data. It was originally developed to store and playback sound recordings exclusively, but later expanded to encompass data storage (CD-ROM), write-once audio and data storage (CD-R), rewritable media (CD-RW), Video Compact Discs (VCD), Super Video Compact Discs (SVCD), PhotoCD, PictureCD, CD-i, and Enhanced CD. Audio CDs and audio CD players have been commercially available since October 1982.Standard CDs have a diameter of 120 millimetres (4.7 in) and can hold up to 80 minutes of uncompressed audio or 700 MB (700 220 bytes) of data. The Mini CD has various diameters ranging from 60 to 80 millimetres (2.4 to 3.1 in); they are sometimes used for CD singles, storing up to 24 minutes of audio or delivering device drivers.CD-ROMs and CD-Rs remain widely used technologies in the computer industry. The CD and its extensions are successful: in 2004, worldwide sales of CD audio, CD-ROM, and CD-R reached about 30 billion discs. By 2007, 200 billion CDs had been sold worldwide.[1] Compact Discs are increasingly being replaced or supplemented by other forms of digital distribution and storage, such as downloading and flash drives, with audio CD sales dropping nearly 50% from their peak in 2000.[2]
DVDs DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions.Pre-recorded DVDs are mass-produced using molding machines that
physically stamp data onto the DVD. Such discs are known as DVD-ROM, because data can only be read and not written nor erased. Blank recordable DVDs (DVD-R and DVD+R) can be recorded once using optical disc recording technologies and supported by optical disc drives and DVD recorders and then function as a DVD-ROM. Rewritable DVDs (DVD-RW, DVD+RW, and DVD-RAM) can be recorded and erased multiple times.DVDs are used in DVD-Video consumer digital video format and in DVD-Audio consumer digital audio format, as well as for authoring AVCHD discs. DVDs containing other types of information may be referred to as DVD data discs.
microforms Microforms are any forms, either films or paper, containing microreproductions[1] of documents for transmission, storage, reading, and printing. Microform images are commonly reduced to about one twenty-fifth of the original document size. For special purposes, greater optical reductions may be used.All microform images may be provided as positives or negatives, more often the latter.Three formats are common: microfilm (reels), aperture cards and microfiche (flat sheets). Microcards, a format no longer produced, were similar to microfiche, but printed on cardboard rather than photographic film. memory cards
A memory card or flash card is an electronic flash memory data storage device used for storing digital information. They are commonly used in many electronic devices, including digital cameras, mobile phones, laptop computers, MP3 players, and video game consoles. They are small, re-recordable, and able to retain data without power.
memory spot chips The Memory Spot chip is an integrated circuit currently in development by Hewlett-Packard. The chip incorporates a central processing unit, random access memory and a wireless receiver, all bundled together in a device 1.4 or 2 mm.[1]The research done to design and build the chip was done in Hewlett-Packard's laboratory in Bristol.Hewlett-Packard says that the chip is so small that it can be built into almost any object, and have proposed several possible uses. These include, but are not limited to:
Ensuring that drugs have not been counterfeited Tagging patients' wristbands in hospitals Authenticating prescription-pill bottles Adding multimedia to postcards Incorporation into books Storing image files on printed pictures to print an identical copy
HP claim that once the units are in mass-production, they may cost as little as one dollar each.No batteries are needed because the chips get their power by induction from the devices which read
the data.Current wireless transfer speeds are 10 Mbit/s.According to magazine Popular Science, the devices "can store and transfer up to four megabytes of data" and should be available on store shelves within two years (Mone 2006).
Awards
2006 - Popular Science Best of What's New - General Innovation[1]
memory sticks
Memory Stick is a removable flash memory card format, launched by Sony in October 1998,[1] and is also used in general to describe the whole family of Memory Sticks. In addition to the original Memory Stick, this family includes the Memory Stick PRO, a revision that allows greater maximum storage capacity and faster file transfer speeds; Memory Stick Duo, a small-form-factor version of the Memory Stick (including the PRO Duo); and the even smaller Memory Stick Micro (M2). In December 2006 Sony added the Memory Stick PRO-HG, a high speed variant of the PRO to be used in high-definition video and still cameras. Memory Stick cards can be used in Sony XDCAM EX camcorders via the MEAD-SD01 adapter.[2]
hard drive
A hard disk drive (HDD; also hard drive or hard disk)[2] is a non-volatile, random access digital data storage device. It features rotating rigid platters on a motordriven spindle within a protective enclosure. Data is magnetically read from and written to the platter by read/write heads that float on a film of air above the platters.Introduced by IBM in 1956, hard disk drives have decreased in cost and physical size over the years while dramatically increasing in capacity. Hard disk drives have been the dominant device for secondary storage of data in general purpose computers since the early 1960s.[3] They have maintained this position because advances in their recording density have kept pace with the requirements for secondary storage.[3] Today's HDDs operate on high-speed serial interfaces; i.e., serial ATA (SATA) or serial attached SCSI (SAS).External storage can be used to expand the HDD of your PC or Mac. It can also be partitioned, allowing users to run other OSs (like Windows, Mac OS X or Linux) Primarily it's used as an additional storage solution for items such as photos, movies and music.
