What's The Difference Between Different Versions of USB ?

The history of USB1.0 USB1.1 USB2.0 USB3.0 USB3.1 USB3.2

USB is the abbreviation of Universal Serial Bus in English. It is a protocol specification for data transmission and an interface technical specification.

USB is a non-profit USB standardization organization (USB Implement Forum, abbreviated as USB-IF) jointly organized by Intel, DEC, NEC, Compaq, IBM, Microsoft, and Northern Telecom at the end of 1996.
USB 1.0 was introduced, followed by the faster USB 1.1 and USB 2.0. In 2008, the USB 3.0 Promoter Group, an industry technology alliance consisting of Intel, Apple, HP, Microsoft, Renesas, STMicroelectronics and Texas Instruments USB 3.0 was released and then moved to USB-IF for management and maintenance. In 2013, USB 3.0 was renamed as USB 3.1 Gen 1 and USB 3.1 Gen 2. The difference between the two is the transfer rate, but they are collectively referred to as USB 3.1. In 2017, USB 3.1 Gen 1 and USB 3.1 Gen 2 were renamed as USB 3.2 Gen respectively. 1 and USB 3.2 Gen 2. At the same time, USB 3.2 Gen 1×2 with a bandwidth of 10Gbps and a USB 3.2 Gen 2×2 with a bandwidth of 20Gbps are added, and these four are collectively referred to as USB 3.2. So far we have entered the era of USB 3.2, where USB 3.2 Gen 1×2 and USB 3.2 Gen 2×2 represent dual channel mode of USB 3.2 Gen 1 and USB 3.2 Gen 2, while USB 3.2 Gen1x1 and USB 3.2 Gen2x1 are USB 3.2 Gen 1 and USB 3.2 Gen 2 single-channel mode.

At present, the name of USB 3.0 has become history, and USB 2.0 still retains.

USB 4.0

Before introducing USB 4.0, we have to mention the Thunderbolt protocol launched by Intel and Apple. Thunderbolt protocol is a combination protocol that integrates DisplayPort protocol (DP for short) and PCI-Express protocol (PCIe for short). The Raiden 1 and Raiden 2 protocols have been launched successively, but the response has been mediocre. Later, the Thunderbolt 3 protocol (TBT3 for short) was launched, and the transmission speed reached 40Gbps. Later, Intel chose to hand over the protocol to the USB-IF Association. In 2019, USB-IF integrated the Thunderbolt 3 protocol (TBT3 for short) on the basis of USB 3.2, and launched USB4 Gen 2×2 and USB4 Gen 3×2. The difference between this name change and the past is that the name of USB 3.2 is still retained. USB4 has doubled the transmission speed of the original USB 3.2, reaching 40Gbps, which is the speed of USB4 Gen 3×2. USB4 supports both USB 3.2 and TBT3 transmission. In short, USB4=USB 3.2+TBT3. Like USB 3.2, USB4 also has single-channel mode and dual-channel mode. The USB4 interface, like the USB 3.2 interface, supports the USB PD fast charging protocol.

USB Transfer Rate

    USB 3.2 Gen1USB 3.2 Gen2USB 4.0
InterfaceUSB 1.0USB 1.1USB 2.0USB 3.2 Gen1x1USB 3.2 Gen1x2USB 3.2 Gen2x1USB 3.2 Gen2x2USB 4 Gen 2×2USB 4 Gen 3×2
Official Standard NameUSB 2.0 Low SpeedUSB 2.0 full SpeedUSB 2.0 High SpeedUSB 3.2 Gen1USB 3.2 Gen2USB 4.0
Official Market NameLow SpeedFull SpeedHigh SpeedUSB 3.2 Gen1USB 3.2 Gen2USB 4.0
Transfer Speed1.5Mbps12Mbps480Mbps5 Gbps10 Gbps10 Gbps20 Gbps20Gbit/s40Gbit/s

The difference between Gen1 and Gen2 Gen3

In one sentence: Gen refers to the transfer rate, Gen1 is 5Gbps, Gen2’s theoretical transfer rate is 10Gbps, USB3.2 Gen2x2 is 20Gbps, USB4 Gen3x2 is 40Gbps, as shown below:

Specification/NameUSB 3.2 Gen 1×1USB 3.2 Gen 2×1USB 3.2 Gen 1×2USB 3.2 Gen 2×2USB 4 Gen 2×2USB 4 Gen 3×2
Historical namingUSB 3.1 Gen 1USB 3.1 Gen 1N/AN/AN/AN/A
Transfer Rate5Gbit/s10Gbit/s10Gbit/s20Gbit/s20Gbit/s40Gbit/s
Lanes quality112222

USB Transportable Interface

The USB interface is divided into three types: Type-A, Type-B and Type-C according to the model. Standard-A belongs to Type-A, Micro-B belongs to Type-B, USB 3.1 interface and before, in addition to Type-C, there are several models such as Type-A and Type-Micro B; Type-MINI B, etc., and to USB The 3.2 interface only supports Type-C. This is because the past connectors such as USB Type-A or Micro-B only support single-channel transmission and cannot support USB3.2 and USB4. The USB transfer speed supports the fastest 40G (20Gbps x2), and can transmit at the same time.

usb cable manufacturer
Plug #1Plug #1Applicability
USB 3.1 Standard-AUSB 3.1 Standard-B






Enhance Superspeed Gen 1×1
Enhance Superspeed Gen 2×1

USB 3.1 Standard-AUSB 3.1 Micro-B
USB 3.1 Standard-AUSB 3.1 Standard-A
USB 3.1 Standard-AUSB 3.1 Type-C
USB 3.1 Micro-AUSB 3.1 Standard-B
USB 3.1 Micro-AUSB 3.1 Micro-B
USB 3.1 Type-CUSB 3.1 Standard-B
USB 3.1 Type-CUSB 3.1 Micro-B
USB 3.2 Type-CUSB 3.2 Type-CEnhance Superspeed Gen 1×1
Enhance Superspeed Gen 1×2
Enhance Superspeed Gen 2×1
Enhance Superspeed Gen 2×2

USB Usage Range

Due to its convenient use, support for hot swap, flexible connection, and independent power supply, USB can be connected to mouse, keyboard, printer, scanner, camera, flash disk, MP3 machine, mobile phone, digital camera, mobile hard disk, external optical floppy drive, USB network card, ADSL Modem, Cable Modem, etc., almost all external devices.