They're a fun thing you can add to your website to display things related to your identity and interests

Some of them include member lists (like mines for example) which is a cool way to find people that enjoy the same things you do altough a lot of them don't and they are merely decorative

I just think these are fun to join but there aren't a lot of them who are still active so I adopted the responsability of creating some for people who like them just as much as I do, you can see a few examples examples of the ones I made on the right side of the screen, if any of those look appealing to you then you can join them by clicking on "Codes" just make sure to read the "How to join section" first I promise it won't take long