Just like a web server, a list server passes on data to users, but this time via e-mail. The 'list' in question, is a list of e-mail addresses belonging to users subscribed to a particular discussion or annoucement group. For example, you could create a discussion list for people who met at a recent event, an announcement list to let your friends know when your website has been updated, and so on. When an authorised person sends an e-mail to the distribution e-mail address associated with a given discussion or announcement list, the list server reads it and automatically forwards it to all the e-mail addresses subscribed to that list.

An e-mail list can be hidden from public view, so that you allow users to subscribe by invitation only. You can also specify that you want to personally approve all subscription requests before users are allowed to join. Alternatively, you can advertise your list to the general public, perhaps as part of an awareness campaign or simply to encourage everyone to come and join in! The easiest way to produce a successful mailing list is to provide a forum where subscribers have a particular interest in common, so think about a focus very carefully when putting your list together and publicising it.