User pages are free-form pages that are yours to create, more or less as you see fit. But we do have a few rules about them — both on this page, and the various pages linked above.

Put simply, the page that starts with User: and ends with your name is your user page. For example, TimeLadyKatie's user page is User:TimeLadyKatie. It's yours to do with as you will, but you don't own it, and it's not in any way private. Think of yourself as the curator of a public page on the internet about you, and create it accordingly.

A better definition

More precisely, user pages are all the pages found in namespace 2. This means they are not just the base page, but all subpages, as well. So Rob T Firefly's user pages are:

User pages are a good way to tell people about your editing skills and interests, but you should limit the personal information you convey on them. Some things flatly aren't allowed on them.

We also strongly discourage users from working primarily on their user pages. If we find that you are spending most of your time at Tardis editing your user page(s), we'll ask you to start editing the rest of the wiki. If you don't, we may, in extreme cases, prevent you from editing here further. That's because this wiki is not your free web host.