Mailing list

A mailing list is a collection of names and addresses used by an individual or an organization to send material to multiple recipients. The term is often extended to include the people subscribed to such a list, so the group of subscribers are referred to as "the mailing list", or simply "the list".

At least two quite different types of mailing lists can be defined: the first one is closer to the literal sense, where a "mailing list" of people is used as a recipient for newsletters, periodicals or advertising. Traditionally this was done through the postal system, but with the rise of e-mail, the electronic mailing list became popular. Such a list is usually unidirectional, with a list owner sending mail and subscribers receiving it.

The second type is sometimes more accurately called a "discussion list": a subcriber uses the mailing list to send messages to all the other subscribers, who may answer in similar fashion. Thus actual discussion and information exchanges can happen. Mailing lists of this type are usually topic-oriented (for example, politics, scientific discussion, joke contests), even if the topic can range from extremely narrow to "whatever you think could interest us". In this they are similar to Usenet newsgroups, and share the same aversion to off-topic messages. The term discussion group encompasses both these types of lists and newsgroups.

Some mailing lists are open to anyone who want to join them, while others require an approval from the list owner before one can join. In even more strict mailing list, every message must be approved by a moderator before being sent to the rest of the subscribers. Moderator approval is usually employed to keep a high average quality of posts and weed out spam. While sometimes people see those restrictions as contrary to freedom of speech, this position is quite unrealistic: a different mailing list with more open rules can be started by anyone.

See also: spamming

• Wikipedia:Mailing lists