Superliminal Advertising!) either have a chip capable of USB or rely on a V-USB implementation, the old fogies of the Arduino world, the Uno and Mega, actually have two chips. An ATMega16u2 takes ...
The 16u2 is normally used as the Arduino Uno’s USB interface ... in all its glory on a modern LCD monitor, driven by a microcontroller, emulating a computer from nearly 40 years ago.