Blue usually indicates USB3 and the black are probably USB2. USB3 is “supposed” to be backwards compatible, and is most of the time, but I’ve ran into a few instances where USB2 devices don’t quite work as well or as reliably when connected to a USB3 port, so a lot of motherboard manufacturers still include a couple USB2 ports for things like keyboards and mice that don’t need the extra speed and may be finnicky on newer ports.
Guess it helps differentiate the USB3 from the USB2.
I was going to ask if the blue one is smaller…?
Blue usually indicates USB3 and the black are probably USB2. USB3 is “supposed” to be backwards compatible, and is most of the time, but I’ve ran into a few instances where USB2 devices don’t quite work as well or as reliably when connected to a USB3 port, so a lot of motherboard manufacturers still include a couple USB2 ports for things like keyboards and mice that don’t need the extra speed and may be finnicky on newer ports.
It’s not smaller but it is faster.