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Such a device is also known under several other names:
Keydrives typically consist of a small plastic package (around 30 to 40 mm long). One end is fitted a single male type-A USB connector. Inside the plastic package is a small, highly cost-engineered, printed circuit board. On this is mounted some simple power circuity and a single surface-mounted integrated circuit (IC). This IC incorporates a flash memory device, related read/write/erase logic, some elementary block-mapping and address-decode logic, and the USB slave-device interface logic. Many keydrives also feature an LED activity indicator. In operation, keydrives are plugged into a normal type-A USB socket, either on a computer or on a USB hub. Keydrives take their power from the USB connection of the PC to which they are connected and do not need batteries. They are impervious to the scratches and dust that have plagued previous forms of portable storage media like compact discs and floppy disks. Most are lightweight and small - about the size of a key or a thumb. They are popular with people who carry data between home and school or work and are quickly replacing the floppy disk as a portable data device. They are also widely used by system and network administrators, who load them with software for troubleshooting and recovery.
Historically, keydrive capacity has ranged from a few megabyteA megabyte is a unit of measurement for computer storage, memory and information; while its exact definition varies, it is in theory equal to one million bytes. The symbol for megabyte is MB (note B for Byte, lowercase b would mean bit). Three definitionss in size up to a few gigabyteA gigabyte (symbol GB is a unit of measurement in computers of one thousand million bytes (the same as one billion bytes in the short scale usage). However, because computers work on the binary system, rather than a gigabyte being 103 Megabytes (1000 MBs)s, although some computers have trouble reading and writing to devices that have more than 2 GB of storage. In 20032003 is a common year starting on Wednesday (link will take you to calendar), and also: The International Year of Freshwater The European Disability Year Summary Perhaps the defining global event of the year 2003 was the Invasion of Iraq launched by the U most keydrives ran at the USB 1.0/1.1 speeds of 1.5 Mbit/s or 12 Mbit/s. 20042004 is a leap year starting on Thursday (the link is to a full 2004 calendar), and has also been designated the: International Year of Rice International Year to Commemorate the Struggle against Slavery and its Abolition Elections are to be held in 73 co saw the release of newer USB keys featuring USB 2.0 interfaces. Although USB 2.0 tops out at 480 Mbits/s, these keydrives are limited by the bandwidth of the underlying flash memory device, with maximum read speeds of around 100 Mbits/s and write speeds a little slower. In ideal conditions, the flash memory in the drives can retain data for 10 years.
KeydriveA keydrive is a small removable data storage device that uses flash memory and a USB connector. Such a device is also known under several other names: keychain drive pen drive pocket drive thumb drive jump drive USB flash drive USB flash memory drive USBs typically have a PC Lock function which enables the USB pen to act as a key to a computer. When the key is removed, the PCPC may stand for: Personal computer, IBM PC, or IBM PC compatible Coastal Patrol, according to its US Navy hull classification symbol Parsec, written pc Percent or per cent, written p. Piano concerto Plaid Cymru ( Welsh nationalist political party) Player locks until it is re-inserted.Like all flash memory devices, keydrives can sustain only a limited number of write/erase cycles before failure. In normal use, mid-range keydrives currently on the market will support several million cycles, although write operations will gradually slow as the device ages. This should be a consideration when using a keydrive as a hard drive to run software or an operating system.
Some keydrives have a physical write protectWrite protection (also known as record protection) is a mechanism that prevents erasure of valuable data by the accidental recording or storing of new data. The mechanism may be a switch, a sliding tab, a removable ring or a break-away tab. Data is protec switch so they may be plugged with impunity into a system that might harbor a virus or worm (when set to write protected).
Keydrives implement the USB "mass storage device" interface, meaning that most modern operating systems can read and write to keydrives without any additional device drivers. This means that Linux (starting from kernel version 2.4, or 2.2 with patches), Mac OS X, Microsoft's Windows Me, Windows 2000, Windows XP, and Windows Server 2003 are all natively able to access keydrives (most of these present the keydrive to the user as simply another removable drive). Windows 98, which was one of the first OSes with much support for USB, needs specialized software for each different type of USB storage device it encounters. Normally only Windows 98 and Windows 95 OSR2 or release version 2 supports USB memory products. MS-DOS (and the older versions of Microsoft windows it underlies) does not include support for USB (nor for USB booting). However there are some amateur projects to include USB support in DOS.
Some computers have the ability to boot up from keydrives, but that capability must be supported in the computer's BIOS.
A few keydrives also function as an MP3 player because the internal architecture of a flash memory based MP3 player is virtually identical to a keydrive. Also, many MP3 players, digital cameras, and other USB devices can also function as a USB flash drive.