USB flash drives are small drives (usually about a half inch wide by 3 inches long) that can store very large amounts of information. As of 2009, high-end flash drives can hold 128 gigabytes, and smaller ones (2 to 8 GB) are inexpensive and commonly available. That has allowed quite large amounts of data to be stored very easily and portably – and, due to the prevalence of USB (Universal Serial Bus) sockets, with near-universal accessibility.
Prior to USB drives, it was difficult and inconvenient to move large amounts of data from place to place. CD-writing technology was almost unavailable on personal computers until the late 1990s; the largest commonly-available portable storage media were floppy disks that could at best hold 1.44 megabytes. Large files (over 1.44 MB) had to be split up across many floppy disks, or put on expensive and rarely-compatible high-density disks, such as Zip disks. Those required special, expensive hardware, which limited their popularity.
Overview of the USB standard
USB 1.0 was introduced in 1995 by a working group of computer companies including Intel, Compaq, Microsoft and IBM. Their intent was to standardize the numerous specialized connectors PCs had at the time and to develop a basic device-connection protocol. The first USB product was released in 1996, and by 1998 the standard had been widely adopted. In 2000 the USB 2.0 standard was released. The second generation of USB had a much faster data-transfer speed.
First-Generation Flash Drives
The first commercially-available USB flash drive was the "ThumbDrive," produced by Singapore company Trek Technology in 2000. Later that year, IBM came out with their own model, the DiskOnKey.
Within two years, more than a dozen companies were marketing USB flash drives, leading to patent clashes. In 2002, Chinese company Netac Technology was awarded the highly-contested Chinese patent for the drive. Trek Technology attempted a number of lawsuits against competing USB drive makers. In 2006 a Singaporean court ordered Trek's competitors to stop selling USB drives, but a UK patent court later that year found against Trek, revoking that company's UK patent for the drive.
The USB 2.0 hardware standard was announced in 2000, although it wasn't commonly available until 2003. It had a significantly faster data transfer speed, about 30 times what USB 1.0 could do (about 30 MB/second, as opposed to 1 MB/second on USB 1.0). USB flash drives had already been increasing steadily in capacity. Faster transfer speeds only encouraged that expansion. The first 1-gigabyte USB flash drives became available in 2004.