Currently valid USB specifications explained:
In order to avoid misunderstandings about the renaming of the USB specifications by the USB-IF (USB Implementers Forum), we would like to explain the differences and the comparable compatible interface. This will help you to map the older spellings that still exist in almost all descriptions, instructions, datasheets and on packaging.
USB 3.2 Gen 1
This standard corresponds to the older designations USB 3.0 and USB 3.1 Gen 1 and enables a max. transfer rate of 5 Gbps (SUPERSPEED). The USB plug types used on computers and notebooks are type A and type C.
USB 3.2 Gen 2
This standard corresponds to the older term USB 3.1 Gen 2 and enables a max. transfer rate of 10 Gbps (SUPERSPEED+). The USB plug types used on computers and notebooks are type A and type C.
USB 3.2 Gen 2x2
This standard enables a maximum transfer rate of 20 Gbps (SUPERSPEED++). The USB plug type used on computers and notebooks is only type C.