Demon Idol is a wiki, a site that functions a lot like Wikipedia. However, for the time being, only players in our AD&D group are able to edit it. But there's a lot that's the same as Wikipedia – pages link to other pages, and you can always see a history of changes to any page by clicking the “Old revisions” button at the right side of the screen.
There are other buttons at the right that are useful too – like the ability to get a PDF of any page, or see what links to the page (these are called “backlinks”).
You'll find a lot of links that are red with a dotted underline. Those are links to pages that don't exist yet, but will someday.
At the top of the screen, below the site logo, you'll find the “Trace” section. This bar will show you links to all the pages you've been to recently. It's like a trail of breadcrumbs, and can be really helpful for flipping between pages.
At the top of the screen and to the right, you'll find a “Recent Changes” page that is just like the “Old revisions” button, but shows the recent changes to all pages across Demon Idol. Also up there, a “Toggle theme” button lets you swap between dark and light mode.