content: USB-C is the physical form factor.  The numbered name (e.g. USB 3.1) is the signaling.  So USB 1.0, USB 2.0, and the former USB 3.0 can all run over USB-A/USB-B, and over USB-C (on the legacy/signaling lines).  USB 3.1 and USB 3.2 (and whatever they're renamed to) can only run over USB-C (I think).  There are also mini/micro versions of USB-A and USB-B, and mini and micro (but not full sized) forms of USB-AB (for devices that can act as both a host and a client). USB-C is great because it's not end-oriented (i.e. the cables are identical on each end and it doesn't matter which end you use, with one exception), it's almost as small as the micro versions of legacy USB connectors, and it's completely backwards compatible with both the physical form factor and allowed signaling (though the standard only allows cables with USB-B on one end and USB-C on the other, because of potential damaging electrical paths that could be made by connecting a legacy host to a legacy host with passive form factor converters).  So yeah, USB-C is super and everything should move to using it (that is, if you ignore the cost of replacing existing devices and the hassle of getting manufacturers to start using it). The signaling protocols are mostly great too, but the games they're playing with naming them are straight up jewry.  It seems obvious that they're going out of their way to make the whole mess confusing and ensure that fly-by-night manufacturers can make all sorts of crap, label it confusingly so you can't tell what it supports until you buy it, and so the USB-IF can collect extra licensing fees from all the confusion.