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.