Same domain or different domains?

domain.com, www.domain.com and subdomain.domain.com

[newsphinx]

Does google treat domain.com, www.domain.com and subdomain.domain.com as same domain or different domains?
Any suggestions will be appreciated!

[Webwork]

My suggestion is that it's likely more complicated than "yes" or "no", considering factors such as content unique to each address - if any - say, between www.example.com and example.com, the date then the address arose (same or separate), G's experience with the widespread unintentional dual existence of www.example.com and example.com, patterns of behavior that might trigger a signal "this is an attempt to game the algo", etc.