Your name. If you haven’t created a user profile yet, you can tell AtariWiki V3 who you are by ‘asserting’ an identity. You wouldn’t lie to us would you?
Note that setting your user name this way isn’t a real method of authentication, because it just sets a cookie in your browser without requiring a password. Depending on the security policy, the wiki may grant you fewer privileges as an “asserted” user. AtariWiki V3 if you would prefer a traditional username and password, which is more secure.

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