What is U disk?

USB flash drive is the most widely used electronic storage product today. The full name is USB flash drive. It is a miniature high-capacity mobile storage product that uses a USB interface and does not require a physical drive. The name of U-disk originated from a new type of storage device produced by Netac Technology, called "U-disk", which uses a USB interface for connection. After the U disk is connected to the USB interface of the computer, the data of the U disk can be exchanged with the computer. And the equipment with similar technology produced after that can no longer be called "USB flash drive" because Netac has already registered the patent, but changed to "USB flash drive" with homophonic sound. Later, the name U disk is widely known because of its simplicity and easy to remember, and it is one of the mobile storage devices.

1. Compared with other portable storage devices, flash U disk has many advantages: it occupies less space, usually operates faster (USB1.1, 2.0, 3.0 standard), can store more data, and has more reliable performance (due to no Mechanical devices), disconnected during reading and writing without damaging the hardware (a floppy disk is immediately damaged when disconnected during reading and writing), only data is lost. This type of disk uses the USB mass storage device standard and has built-in support in operating systems such as Linux, Mac OS X, Unix, and Windows.

2. U disks usually use ABS plastic or metal shells. With the improvement of the public's aesthetic ability, there are also various shell materials. For example, the wooden case, which contains a small printed circuit board inside, allows the flash drive to be small enough to fit in a pocket like a key ring charm or strung on a neck lanyard. Only the USB connector protrudes out of the case and is usually covered by a small cover. Most USB sticks use a standard Type-A USB connector, which allows them to plug directly into a USB port on a PC.

3. To access data on a USB flash drive, you must connect the USB flash drive to a computer; either directly to the computer's built-in USB controller or to a USB hub. The flash drive will only boot when plugged into the USB port, and the required power is also supplied by the USB connection.

4. The current U disks all support the USB2.0 standard, but due to the technical limitations of NAND flash memory, their read and write speeds cannot reach the maximum transfer speed of 480Mb/s supported by the standard. The fastest flash drives use dual-channel controllers, but they're still a notch short of the maximum transfer rates that hard drives, or USB 2.0, can provide. The highest transfer rate is about 20~40 MB/s, while the average file transfer speed is about 10 MB/s.

The main purpose of the U disk is to store data. After the efforts of fans and businesses, the U disk has developed more functions: encrypted U disk, boot U disk, antivirus U disk, temperature measurement U disk and music U disk, etc.

A. Driverless

Driverless products can be used normally under Windows 98/Me/2000/XP and Linux, Mac OS and other systems that support USB Mass Storage protocol, and only need to install drivers under Windows 98 system, and the operating system above Windows Me It can be correctly recognized and used by the system without installing drivers, which truly embodies the convenience of "plug and play" of USB devices. Most U disks on the market are driverless, and users have a lot of choice. U disks from Xinghengguang are good choices.

B. Encrypted

In addition to encrypting the stored content, the encrypted U disk can also be used as an ordinary U disk. There are generally two types: one is hardware encryption, such as fingerprint recognition encrypted U disk, this kind of U disk is expensive, for users in special departments, generally speaking, the security of hardware encryption is better; the other is It is software encryption. Software encryption can specially divide a hidden partition (encrypted partition) in the U disk to store the files to be encrypted, or it can only encrypt a single file without dividing the partition, and the encrypted partition or encrypted single file cannot be opened without a password. , so as to play a role in confidentiality.

C. Start-up

The appearance of the bootable U disk makes people look at this portable product with admiration. As the name suggests, the bootable U disk has added the function of booting the system, which makes up for the defect that the encrypted and non-drive U disk cannot start the system. It is the appearance of this product that has accelerated the process of floppy drives being eliminated. To boot the system, the USB flash drive must emulate a USB peripheral. For example, the bootable U disk on the market mainly relies on the simulation of USB_HDD to realize the system boot. Booting the system by simulating USB_HDD has an advantage: after the system is started, the U disk is regarded as a hard disk, and the user can maximize the space of the U disk. This also fully reflects the characteristics of the large capacity of the U disk. This kind of U disk with multi-boot function can not only be used for desktop computers, but also widely used in notebook computers with external USB floppy drives. With this kind of U disk, notebooks can completely eliminate floppy drives and even optical drives.