ListservThere are thousands of special interest discussion groups on the Internet, organized by topic. Each of these groups has a mailing list of members who have voluntarily subscribed to the group by submitting their e-mail address. Listserv is the name of a package that automatically maintains the lists of these groups.
Listserv acts as a centralized server to all members on the mailing list, thereby facilitating communications between the group's members. What this means is that when one member of the group submits a message to the listserv, it is automatically forwarded to everyone else on the list.
Anyone with Internet e-mail access possesses the technical power to join a listserv mailing list. However, some mailing lists are "closed", meaning that they will reject your request for subscription, and some are "by-owner", meaning that listserv forwards your request to the mailing list owner, who then decides whether or not to add you to the list.
Listserv was devised by the BITNET Information Centre to facilitate the distribution of e-mail between members of a special interest mailing list. Unlike today's listserv (technically called "revised listserv"), the original listserv required that a human administrator took care of processing all requests for subscription and unsubscription to the mailing list. Today's revised listserv is much more efficient than its predecessor because requests for subscription and unsubscription are processed directly by the listserv, eliminating administrative meddling. While there is sometimes a person called a moderator who manages the list, making sure that all of the messages are suitable for distribution, this is no longer a requirement.
Listserv in its current form is also more effective because it has been decentralized; mailing lists can be managed by servers at a variety of sites rather than on a single server. Although these servers may manage different segments of the mailing list's constituency, they are all connected, so that a command sent to one is passed on to the others. Listserv also has a database file for each mailing list; all messages from the mailing list are archived and retrievable by search.
Listservs can be very economical if you are using a commercial on-line service. Instead of paying for online time while you read through discussion group messages, you can subscribe to a listserv, receive the messages through your e-mail, and download them so you can read them off-line. So although the communications are in a somewhat different form, you get the same benefits of shared information and social interaction.
If you plan to read every single message that comes through your box from this mailing list, then listserv is ideal. However, if you are only mildly interested in a listserv topic, it can be irritating to have to deal with the volume of e-mail that you may receive. Since some listservs are very active, spewing out more than twenty messages a day, it's no surprise that the most common complaint about using a listserv is the potential overabundance of e-mail. However, many listservs now offer a digest of their messages, which eliminates this problem.
After you decide which mailing list you would like to subscribe to (see the links under URLs), the easiest way to join the list is to send e-mail to the listserv. The address to subscribe to a mailing list will probably look something like this: "LISTSERV@host-id," (host-id" being the address of the computer that "hosts" the list). This is an address that you will use only if you want to unsubscribe or are having problems with the list. When you subscribe, the listserv will automatically send you the e-mail address of the mailing list, which is where you will send all the messages you want distributed to the discussion group.
Your e-mail message to the listserv will contain a simple series of commands telling it to subscribe (minus the brackets):
subscribe [name of list] [your first name] [your last name] to unsubscribe, send the message: unsubscribe [name of list] [your first name] [your last name]
The only commands that listserv pays attention to are those in the body of the message; it completely ignores anything you may have written in the subject line. In addition, it only processes one command per line.