This seems like an instance where visualization confuses more than clarifies. The paragraph at the bottom of the page presented as a table would be more comprehensible.
Thanks Dave! I share many of the sentiments in your writeup, especially about existing tutorials. Admittedly, I have been impressed by the quality of a few of the tutorials that others have suggested here. Will let you know if I think of anything!
Slightly embarrassing -- but the problem may be that the site isn't compatible with FireFox (at least pre-v63 FireFox). The site makes use of custom HTML elements which are not supported by default in pre-v63 FireFox (https://developer.mozilla.org/en-US/docs/Web/Web_Components/...). The good news is that all you need to do is to turn on a flag as set forth in the link provided. The bad news is that many other less tech-savvy people are going to be stymied by this.
edit: the site will now warn you if your browser is incompatible.
In 1998 you had to be running Windows. Now you can run any OS, even if the browser you have to use for a certain site isn't your favorite. It's an improvement.
People have always wanted to use "the web" as an application platform. It didn't work that well in 1998, but it's pretty good now. Progress has been made.
All the blue boxes are actually interactive code editors. You can run arbitrary queries against the dataset in them. I changed some of the wording to make it clearer. Hopefully that helps!