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Electronic Discussion Groups

Public electronic discussion groups number in the thousands and cover almost every scholarly, professional, and avocational topic imaginable. Users from around the world can participate in these discussions whenever and from wherever they prefer. In addition, untold numbers of private discussion groups exist to promote communication among defined sets of participants.

Email discussion groups

A variety of types of email discussion groups are in use on the Internet and at Penn. Information about setting them up can be found on ISC's Mailing Lists site.

  • Personal alias lists. Personal alias lists can be created in most email products. They allow the creator (owner) to send messages to a single address and have them go to all the individuals on the list.
  • Reflector lists. Some email servers, including campus servers such as Pobox, allow for "reflector lists," which are similar to personal alias lists except that anyone, not only the owner, can send a message to the list.
  • Listserves. A more sophisticated type of list, known as a listserve, has the same basic functionality as the other lists but uses list server software to provide more formal administration tools: the ability to restrict list membership and activities, message archiving, and other features. Some commonly used list server systems are listserv, majordomo, and LISTPROC. As you explore email discussion groups, you will discover that the administrative addresses of many discussion groups include one or the other of these terms.

In addition, ISC and the Registrar's Office provide course email lists in selected Schools. Details can be found on ISC's Class Mailing List Service page .

Once you've subscribed to an email list, postings come directly to your email inbox -- you don't have to logon somewhere else to find for them. At the same time, it's up to you to manage the messages you receive, saving and deleting as necessary. Otherwise you may find your mailbox inundated with mail, particularly if you subscribe to several active lists. Many email lists are moderated (the messages are reviewed for appropriate content by the moderator or collected into a digest before going out to the group). Thus the likelihood of trivial or repetitive discussionis reduced.

Participating in email groups

There are various ways to find email discussion groups to subscribe to. Web sites dedicated to related topics are one good source of list addresses. Another is FAQs (frequently asked questions). A third is directories such as CataList, a searchable catalog of more than 8,000 public lists, and the Directory of Scholarly and Professional E-Conferences (useful but last updated in 2002). Finally, you can send email to as follows: leave the subject line blank and In the body of the message, type list global, a space, and then a word or partial word describing the type of listserv you're looking for. For example, if you were looking for a jazz-related listserv, you'd type list global jazz.

Email discussion groups available to the Internet public usually maintain two network addresses -- one accepts subscriptions and administrative commands; the other accepts email postings relevant to the discussion topic. The examples in the next paragraph illustrate the use of the two addresses. New users frequently confuse them, and send their subscribe or unsubscribe commands to the posting address rather than to the administrative address. For Penn students in courses that have a discussion group set up this is generally not a problem: they're usually subscribed automatically upon enrollment and get the correct posting address from their instructor.

To subscribe to a listserv discussion, you would send a request to the list's administrative address -- listserv@name of listserv -- and include the following line in the body of your message:

subscribe name of listserv

To post messages once you've subscribed, you would address them to the name of the list followed by the machine name. Because lists vary in the way they are configured and managed, the above commands won't work for all lists.

When you subscribe to a list you will usually get a welcome message with information about where to get help, how to unsubscribe, etc. Be sure to save that message -- you are bound to need it some day. You will also get a more technical message that you can safely discard.

Some final words about email discussion groups. Some messages require personal responses to the original sender; for other messages, it is more appropriate to send your response to the list. Be careful when using your mailer's reply command. Sometimes your reply will go to the entire list by default; other times, replies are sent to the originator by default. Exactly what happens depends on how the list was set up. If you send a message to a list you are subscribed to and don't get a copy in your own mailbox, don't worry. Some lists are configured so that senders do not get their own postings.

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