Mailing list members are users that get mass emails, including weekly or monthly newsletters. Depending on the software that’s used to manage a particular list, they may have joined personally, expressing their categorical permission to be included in the mailing list, or they may have been added manually. The latter means that they will technically receive unsolicited messages. Traditionally, subscribers can be managed by the mailing list admin who can authorize or delete them, or they can unsubscribe manually if they do not want to receive emails from now on. All subscribers will invariably receive the same content provided that they belong to one and the same mailing list, but a single subscriber will never be able to see the rest of the mailing list subscribers in the "To" field of the email.