[Mailman-Users] how does mailman get its mails?

[MAILMAN Server]

really silly question indeed :(
If I have multiple mailing lists called, a-list b-list ...
do I have to have mail-alias for all this mail-idents on my mail-server?
also, the default setting for the mailbox of my sendmail is /var/mail/somebody,

I mean the location of mailboxes.  Does mailman know how to find this by itself,
or do i have to configure it?

thank you vey much!