A flash drive, also known as a USB drive or pen drive, is a small, portable storage device that can store and transfer data through a Universal Serial Bus (USB) interface. The term “flash” refers to the type of memory used in the device – NAND flash memory - which allows for fast read and write speeds and makes it possible to store large amounts of data on a compact, removable storage medium. Flash drives are widely used as an alternative to traditional external hard drives or optical discs due to their convenience, portability, and ease of use.