It’s indeed that abbreviation. Most controllers use Midi, which is effectively a control language, to talk to and receive info from the DJ Software. While midi is fine, it needs to be mapped (i.e. for every knob fader etx the DJ Software needs to be told what it does and how to respond) and there are a few other bits and pieces. In a HID setup, all the functions of the device are “hard-coded”, just like a scroll-wheel on a mouse is. Especially the feedback to built-in screens on mediaplayers like CDJs is a big advantage in HID mode usually.
It’s well beyond this forum and this post to go into details, but suffice to say that true HID support for a device by your DJ software is preferably to a hybrid or midi connection (imho).
So, it’s not a catchall. Some mediaplayers (as said, typically the CDJs) can be set to work in HID mode with certain software. Most all controllers are midi though. Most mixers are nothing as they usually have no digital options. Bar a few high end models that might have midi.
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