I don't fully understand panopticlick results. My machines always get uniquely identified by screen size (which I sort of understand, but find doubtful) and fon

I don't fully understand panopticlick results. My machines always get uniquely identified by screen size (which I sort of understand, but find doubtful) and fonts installed. The latter I find very confusing since it often lists a set of garden variety Windows fonts, which I don't even have installed on my machine.