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.
Important note: Penn's NetNews
service was retired on June 30, 2008. Documentation to help users
of this service transition to other services can be found at:
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
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.
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
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 email@example.com 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.