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 is 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.
When similar or identical material is sent out to all subscribers on a mailing-list, it is often referred to as a mailshot or blast. A list for such use can also be referred to as a distribution list.
In legitimate (non-spam) mailing lists, the individual can subscribe or unsubscribe themselves.