A mailing list is a collection of email addresses that get the very same email simultaneously. When you send an email message to the mailing list address, your message will be forwarded to all the email addresses on that mailing list automatically, but none of the receivers will know who the other recipients are. In the general case, users have to subscribe to a list, but occasionally email addresses are added manually without the permission of their owners. Depending on the particular list administration software, you may also be able to greenlight new mailing list subscribers, so users will not be able to join your mailing list unless you okay their request. The mailing list feature is rather handy in case you’d like to send newsletters on a regular basis or some other type of regular publications to customers, since you will have to send out only one email message and all of the mailing list subscribers will get it instantaneously. This way, you won’t need to insert a huge number of email addresses manually.