A mailing list (Engl. Mailing list ) offers a closed group of people the opportunity to exchange messages in letter form, so networking with electronic means. This exchange of messages is public within the group. Mailing lists are particularly common on the Internet , where they are implemented via e-mail . Mailing lists are historically the archetype of newsgroups and Internet forums , but for certain purposes they are still the method of choice today.
Mailing lists are used for multidirectional communication between rather equal participants. It differs from newsletters and circulars in that the latter are more of a unidirectional distributor of news from a single source. Gradual deviations from these principles exist so that the transition between mailing list and newsletter is fluid.
Mailing list by email
The mailing list is a list of e-mail addresses that has an e-mail address of its own. In this way, each member of the mailing list can send a message to all other members without having to address them individually and even without having to know their e-mail addresses. To do this, the Mail Transfer Agent forwards an incoming e-mail to the address of the mailing list to all members of the mailing list. Depending on the settings of the mailing list, this happens immediately after sending, after approval by a moderator or as a regular, e.g. B. daily, digest .
Mailing lists are an Internet standard whose automated use is defined in RFC 821 from 1982, for example . Mail transfer agents are caused by the command EXPN to convert addresses of known mailing lists into the member addresses.
Sign in and sign out
As a rule, a user has to register with a mailing list in order to receive the news distributed there or in order to be able to send messages to the participants of the list himself. For the application itself (. Engl subscribe ) are very used different methods - from an entry by hand after informal application to fully automated process with confirmed opt-in . The administrator of the list determines whether a user is allowed to log in at all by configuring the server.
As with subscribing, there are also a number of procedures for unsubscribing . Often, when subscribing to a mailing list, the subscriber to a mailing list automatically receives a message describing how to unsubscribe. Some lists also automatically write this note in the header of the e-mail or under every post that is distributed via the list. In most cases the subscriber has to send an e-mail with an unsubscribe command to a special address, in some cases he can also unsubscribe via a web interface . Under no circumstances should a subscriber write e-mails to the list asking them to unsubscribe, as this would unnecessarily bother the other subscribers. There are also lists from which the subscriber cannot or can only have his address removed with great difficulty.
Whether a logged-in user is allowed to read, write or both is determined by the list administrator through the configuration of the server. So find z. B. Lists that anyone can read (via a web interface), but only registered users can write to. Some mailing lists are supervised by a moderator who reviews all or incoming mails from certain participants before approving the forwarding.
Web interface and archive
In contrast to the e-mail distribution list , a mailing list has its own e-mail inbox in which all messages sent via the mailing list are stored. This email archive can usually be accessed via a web interface. In this way, a member of the mailing list can also read e-mails sent through the mailing list before subscribing to the mailing list.
Abuse and Protective Measures
Mailing lists are sometimes misused by malicious third parties entering the email address of a recipient in various lists - without the recipient's consent - so that they will from now on regularly receive unwanted emails from this list (so-called list linking).
The problem can be easily avoided by the operator of the list by stipulating a confirmed opt-in procedure for registration. The recipient only receives one e-mail per list, to which he would have to react in order to be entered in the list's distribution list in the future, which he can simply omit. Recipients entered involuntarily do not need to deregister.
It is much more time-consuming for the recipient if the list operator does not opt-in . In this case, the recipient has to remove himself from all lists or have himself removed from the list by the administrators, which with some dubious operators is not possible or only possible with great effort. In both cases, this is an extremely annoying and, above all, time-consuming matter - especially since there is a risk that the address of the unwilling recipient will be re-entered in this or other email distribution lists. In extreme cases, an e-mail address can become largely unusable in this way due to the undesirably high volume of mail.
Mailing lists can also be misused by properly registered participants by sending e-mails with a purely advertising character ( UCE ), content that violates netiquette or is unrelated to the topic. The administrator can warn such senders and exclude them in the event of repetition or, if the mailing software offers this option, switch their status individually to "moderated", i.e. check their e-mails before forwarding them. (More general information on moderation can be found in the Internet forum article .) Some lists only allow all participants to switch to this mode. However, this causes expenditure of time and effort for the administrator, delays in delivery (which then usually take place "in packages" and impairs the liveliness of discussions), and last but not least, the participants can get the impression of censorship.
Comparison with forums and Usenet news
Mailing lists are comparable to forums or Usenet . The advantage over a web forum is that the posts can be read and written offline . One advantage over Usenet is that a list server (the program that distributes the news) is much easier to set up than a newsgroup on Usenet. Most Internet users have a program for reading news ( newsreader ) as part of their web browser , but they are not familiar with this option and cannot operate it. In addition, they would have to have Usenet access (available almost automatically at universities, but otherwise hardly) or subscribe to one for a fee.
Certain rules for the formatting of messages have become established in Usenet as well as on mailing lists. A summary of rules, compliance with which contributes to better readability and comprehensibility of the "course of the conversation" (thread) is known as netiquette . A frequent violation of this netiquette is the superfluous use of full quotes in replies or so-called thread hijacking , whereby the sender starts a new topic as a reply within a running thread instead of starting a new thread with a new mail.
Frequently used mailing list programs:
Other programs and mailing list providers are: Dada Mail , Dgroups , Email marketing software , Google Groups , GroupServer , Mailing list , MSN Groups , Online consultation , Regroup , SmartList , squeeze page and Yahoo! Groups .
Encrypted mailing lists
There are now some approaches to encrypting mailing lists. So far, however, only a few mailing list providers support these. An example of a functioning encryption is Sympa, which can be used for this together with S / MIME certificates.