A mailing list is a list of email addresses that receive the same email message simultaneously. When you send an email message to the mailing list address, your message will be forwarded to all the addresses on that mailing list automatically, but none of the receivers will learn who the other recipients are. Generally, one has to join a mailing list, but sometimes mailboxes are added manually without the awareness of their owners. Depending on the specific mailing list administration software, you may also be able to approve new mailing list subscribers, so users cannot register for your mailing list unless you authorize their signup request. The mailing list option is rather useful in case you’d like to send regular newsletters or some other kind of periodic publications to customers, since you will have to send only one e-mail message and all of the mailing list subscribers will receive it immediately. As a result, you will not have to enter many mailboxes manually.