An admin can edit a user on this page, change his username, first/last names, email etc.
You can also edit the user permissions: make him an admin or a technician.
Users can upload their own avatar images, if avatars are enabled in your Helpdesk. The avatar image should be in a form of square - 100x100 pixels and 50Kb max. If users don't upload custom avatar images, Helpdesk will try to obtain the image from Gravatar.com using user's email address. If you are using Windows auth, helpdesk will try to get user avatars from Aactive Directory.