<Table> <Tr> <Td> </Td> <Td> Some of this article's listed sources may not be reliable . Please help this article by looking for better, more reliable sources . Unreliable citations may be challenged or deleted . (June 2017) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> Some of this article's listed sources may not be reliable . Please help this article by looking for better, more reliable sources . Unreliable citations may be challenged or deleted . (June 2017) (Learn how and when to remove this template message) </Td> </Tr> <P> A USB flash drive, also variously known as a thumb drive, pen drive, jump drive, disk key, disk on key, flash - drive, memory stick or USB memory, is a data storage device that includes flash memory with an integrated USB interface . It is typically removable, rewritable and much smaller than an optical disc . Most weigh less than an ounce (approx . 30g). Since first appearing on the market in late 2000, as with virtually all other computer memory devices, storage capacities have risen while prices have dropped . As of March 2016, flash drives with anywhere from 8 to 256 GB are frequently sold; less frequent are 512 GB and 1 TB units . Storage capacities as large as 2 TB are planned, with steady improvements in size and price per capacity expected . Some allow up to 100,000 write / erase cycles, depending on the exact type of memory chip used, and are thought to last between 10 and 100 years under normal circumstances . shelf storage time . </P> <P> USB flash drives are often used for the same purposes for which floppy disks or CDs were once used; i.e. for storage, data back - up and transfer of computer files . They are smaller, faster, have thousands of times more capacity, and are more durable and reliable because they have no moving parts . Additionally, they are immune to electromagnetic interference (unlike floppy disks), and are unharmed by surface scratches (unlike CDs). Until about 2005, most desktop and laptop computers were supplied with floppy disk drives in addition to USB ports, but floppy disk drives have become obsolete after widespread adoption of USB ports and the larger USB drive capacity compared to the 1.44 MB 3.5 - inch floppy disk . </P>

Which type of storage technology is used in pen drives