Userboxes are boxes you can display on your user profile page to show some aspect of yourself, your game characters, or just for fun.
The standard userbox is here: Template:StandardUserbox
Userboxes are stored in the "Userbox" namespace.
To create a userbox, visit Template:Ifexist (which will only exist if the feature is active on the wiki). You can choose content, colouring and images from here. The text area accepts wikitext.
To add a userbox to your profile page, visit Template:Ifexist and click on the userbox you wish to add.
You can embed them in a page using [[Userbox:<name>]].
Currently active userboxes
You can view your currently active userboxes on Userbox List.