A mailing list is a facility whereby a message sent to a special address, the list posting address, is redistributed to a number of other addresses, the list members' addresses.
So sending a message to a single address can reach many people. Lists are typically used for distributing information or as discussion groups.
In the University we support mailing lists on the Sympa list service, which is capable of providing thousands of lists and is flexible to allow list owners to create dynamic lists from database queries and LDAP directory lookups e.g. to create lists from class lists or year of study or school code. Lists can be administered using any web browser or via commands sent in email messages.