Internet mailing list subscribers are persons that get bulk email messages, including weekly and/or monthly newsletters. Based on the mailing list management software application that is used to manage a particular list, they may have joined personally, expressing their categorical consent to be part of the mailing list, or they may have been added manually. The latter implies that they will de facto receive unsolicited messages. Generally, mailing list members can be managed by the mailing list administrator who can add or delete them, or they can unsubscribe manually if they do not want to receive emails from now on. All mailing list members will invariably receive one and the same content provided that they are part of one and the same mailing list, but a single member will never be able to see the remaining mailing list subscribers in the "To" field of the message.