So typically - the more pixels - the more things you can fit on your screen.  So in rough terms - a 4K screen has 4 times the screen real-estate compared to an HD screen - so it could potentially show 4 times the amount of stuff.   The other side of that though, is that (assuming the two screens are the same size) everything is 4 times smaller on the 4k screen - which at 17", 21", 23", or even 27" is functionally too small.  To counter this - in the screen settings (In windows) - there is a scal