How to use an Arcade interactive demo

When you get to interactive demos in an article, you'll see the text:

Interactive Demo below

1. Progress through the Arcade demo by clicking on the purple, pulsing circle indicators called "hotspots".
2. Read the hotspot text BEFORE clicking the hotspot. There is not a way to move back to the previous hotspot without restarting the demo. 
3. If you want to go through the interactive demo again, you can click "Replay demo" icon  in the top bar of the Arcade

Interactive Demo below