The multiple email forward is an email forward which forwards mail to small groups of up to 15 people, i.e.:
sales@yourname.com -> user@yourname.com,
-> user2@yourname.com,
-> user@yourisp.com,
-> user@anotherisp.com,
-> user2@anotherisp.com
All mail sent to the multiple email forward is forwarded to all recipients.