A mailing list is a list of email addresses that receive one and the same message simultaneously. When you send an email to the mailing list address, your message will be redirected to all the addresses on that mailing list automatically, but none of the receivers will learn who the other recipients are. Generally, people have to register for a list, but sometimes email addresses are added manually without their owners’ approval. Depending on the specific list administration software, you may also be able to add new subscribers, so users will not be able to subscribe to your mailing list unless you approve their request. The mailing list functionality is rather valuable in case you would like to send newsletters on a regular basis or some other type of regular publications to customers, as you’ll have to send one single email message and all the mailing list subscribers will receive it instantaneously. This way, you will not have to write lots of mailboxes manually.