Basic concepts

A Mail for Domain user who connected and verified at least one domain using the Yandex.Mail for Domain interface. Administrators can manage their domains and the email on them (for example, enable email on a domain for an organization or the users of a specific website).
An administrator can assign proxies — grant specific users access to manage email on a particular domain.

A Mail for Domain user who manages (registers, parks, and so on) the domains of administrators and their email.

Domain administrator proxy

A Mail for Domain user who can manage mailboxes, but cannot manage the domain itself and its settings.

Mailing list
An email address that is associated with a group of mailboxes. Messages that are sent to the mailing list will be delivered to each of the associated mailboxes.
DKIM (DomainKeys Identified Mail)
A mechanism for including a digital signature with email messages that identifies the sender's domain.