Flash drive

A flash or “thumb” drive is a small data storage device that uses semiconductor flash memory rather than a disk drive. It is connected to a digital device using the universal serial bus (see usb). Because most computers, digital cameras, and other digital devices have USB ports, a flash drive is a convenient way to provide up to 16 GB (as of 2007) of low power, rewritable memory. Flash drives first appeared in late 2000.

Flash drives can use a separate USB cable (useful when several devices need to be connected to closely spaced USB ports) or simply have a connector that plugs directly into the port. Many people who regularly work with several computers carry their backup data or even a complete oper-ating system (such as Linux) on a flash drive, perhaps con-nected to their keyring.

In Windows Vista some recent flash drives can be used to provide an additional system memory cache through a feature called ReadyBoost.

Flash drives can also be built into portable devices, including video and audio players. A competing technol-ogy (particularly found in digital cameras and PDAs) is the Secure Digital (SD) memory card developed by Matsushita, SanDisk, and Toshiba, which offers comparable capacity but is proprietary and requires a special interface.

For high-security applications, flash drives can include built-in encryption or fingerprint readers (see biometrics). However, as with other readily portable media, unsecured flash drives containing sensitive data pose a real risk to many organizations. Under development by SanDisk and Intel are larger flash drives (32 or 80 GB) suitable for replacing hard drives in laptops. The benefits are lower weight and power consumption.