USB Protocols:

  • USB4 2.0 (up to 80Gbps) – in fact, the external device seems to become internal, for specific high-performance tasks. Obviously not for USB flash drives.
  • USB4 (up to 40Gbps on special cables) – in fact, the external device seems to become internal, for specific high-performance tasks. Obviously not for USB flash drives.
  • USB 3.2 (USB 3.2 Gen2x2, 20Gbps) is needed for very fast devices (graphics?) or a large number of them on one wire. Even for an SSD, this is too much.
  • USB 3.1 (USB 3.2 Gen2, 10Gbps) is too much for USB flash drives and SD cards (3.0 is enough for them).
  • USB 3.0 (USB 3.2 Gen1, 5Gbps) in theory should cover all USB flash drives and SD cards, and many SSD drives. But this is just a transmission protocol. There is also the speed of the flash drive itself. Therefore, it usually makes sense to take USB 3.1 flash drives, they are usually faster. And just look at the stated speeds on the box.
  • USB 2.0 is only for transferring test documents for printing, it is better not to use it for the rest. Or as an option for offline watching movies: they are very cheap, you can record a lot of movies (albeit for a long time), and then watch them on a projector, for example.

For flash drives, the choice is as follows:

  • USB 2.0 – print/text documents, archive, media archive.
  • USB 3.1 / USB 3.2 Gen2 – usually fast flash drives, but it is important to look at the stated speeds (reading more than 100Mb/s, writing more than 50Mb/s).
  • USB 3.0 (USB 3.2 Gen1) – there may potentially be a fast flash drive, but due to marketing it is usually already 3.1, and here the average speed of the flash drive (read 40Mb/s, write 20Mb/s).

SD card or USB flash drive:

  • For constant use, a large USB flash drive is dangling – inconvenient for constant connection. So a microflash or an SD card.
  • To transfer data, it is better to use a regular USB flash drive – a convenient size, you can write something (using a sticker).
  • In practice, SD cards are less reliable (or I just buy more unreliable ones).
  • Usually USB SD card readers for a computer are based on USB 2.0 – so they are slower in a computer than flash drives.
  • But where there are connectors for SD cards (Raspberry Pi, minicomputers, macbooks), they are more often faster than USB flash drives.
  • USB flash drives are usually cheaper, sometimes up to 2 times.

Yes, and now all SD cards / flash drives / SSDs need to be checked for size forgery: there are too many fakes (for example, he really writes in the first X GB, and loses everything further, although the OS says that everything is OK - so you can really lose data). There are different programs for different operating systems. macOS / Linux: f3 (f3write -> f3read: checks write/read and shows the speed).

TF cards are the same SD cards, only the name is not licensed.

Well, it’s absolutely optional: if it’s not clear where the place has gone, then there is a console utility `ncdu’ for this.