brief introduction
U disk, full name of USB flash drive, English name of USB flash drive. It is a miniature large-capacity mobile storage product that uses USB interface and does not need physical drive. It can be connected with computer through USB interface to realize plug and play. The name of USB flash drive comes from a new storage device produced by Netac Technology, which is called "USB flash drive" and is connected by USB interface. After the USB flash drive is connected to the USB interface of the computer, the data of the USB flash drive can be exchanged with the computer. However, the equipment with similar technology produced later, because Netac has registered the patent, can no longer be called "USB flash drive", but changed its name to "USB flash drive". Later, the name U disk was widely known because it was easy to remember, and it was one of the mobile storage devices [2].
Compared with other portable storage devices, flashu disk has many advantages: it takes up less space, usually runs faster (USB 1. 1, 2.0, 3.0 standard), can store more data, and has reliable performance (because there is no mechanical equipment). When disconnected during reading and writing, the hardware will not be damaged (the floppy disk will be damaged immediately during reading and writing), but the data will be lost. This kind of disk adopts USB mass storage device standard, and has built-in support in modern operating systems such as Linux, Mac OS X, Unix, Windows200, XP and Win7 [2].
U disk usually adopts ABS plastic or metal shell, and contains a small printed circuit board inside, so that the flash drive is small enough to be put in a pocket like a key chain ornament or strung on a neck rope. Only the USB connector protrudes from the protective case, usually covered by a small cover. Most USB flash drives use standard A-type USB connectors, which allows them to be directly plugged into the USB port of a personal computer [2].
To access the data of the USB flash drive, you must connect the USB flash drive to the computer; Whether it is a built-in USB controller directly connected to the computer or a USB hub. Only when the USB port is plugged in, the U disk will start, and the required power supply is provided by the USB connection [2].