The other pages work the odds out exactly. Here the dice are rolled for real, one at a time or a hundred thousand at once, so you can watch the luck of a few rolls turn into the exact odds.
Bars: how often each total came up in your rolls. Dots: how often it should, worked out exactly. A few rolls are lumpy; many rolls sit on the dots.
The line is your average so far. The shaded funnel is where it lands 95 times in 100 after that many rolls: wide at first, narrowing toward the exact average.
The dice are rolled in your browser with its random number generator; the exact odds come from the same engine as the other pages.