@unripe @raulinbonn You can get converters for them. Mine is a PS/2 keyboard, for example, it needs a PS/2 to USB converter to work. Some of them need a couple of converters though, so a bit of a hobbled together mess, but it's usually doable!

@unripe @babe My PC has a motherboard (Asus Maximus VIII Ranger) which still had a PS/2 port. I built this PC myself early 2017, didn't choose that motherboard because of that (didn't have the Model M yet back then, got it couple of years later,) but luckily I could plug it in directly to my PC as it was.