LISTSERV
The term Listserv has been used to refer to electronic mailing list software applications in general, but is more properly applied to a few early instances of such software, which allows a sender to send one email to a list, which then transparently sends it on to the addresses of the subscribers to the list.
The original Listserv software, the Bitnic Listserv, allowed mailing lists to be implemented on IBM VM mainframes and was developed by Ira Fuchs, Daniel Oberst, and Ricky Hernandez in 1984. This mailing list service was known as Listserv@Bitnic and quickly became a key service on the BITNET network. It provided functionality similar to a UNIX Sendmail alias and, as with Sendmail, subscriptions were managed manually.
In 1986, Éric Thomas developed an independent application, originally named "Revised Listserv", which was the first automated mailing list management application. Prior to Revised Listserv, email lists were managed manually. To join or leave a list, people would write to a list administrator and ask to be added or removed, a process that became more time-consuming as discussion lists grew in popularity.
By 1987, the users of the Bitnic Listserv had migrated to Thomas' version.
Listserv was freeware from 1986 through 1993 and is now a commercial product developed by L-Soft, a company founded by Thomas in 1994. A free version limited to ten lists of up to 500 subscribers each can be downloaded from the company's web site.
Several other list-management tools were subsequently developed, such as Lyris ListManager in 1997, Sympa in 1997, GNU Mailman in 1998, and Gaggle in 2015.
Automated mailing list management
In 1986, Éric Thomas developed the concept of an automated mailing list manager. Whilst a student at École Centrale Paris, he developed the software now known as LISTSERV. Some of the early software features allowed joining or leaving a list without the need for human administration. The list owner could also add or remove subscribers, and edit templates for both welcome and system messages. Amongst other innovations LISTSERV introduced double opt-in in 1993 and the first spam filter in 1995.After the release of Thomas' LISTSERV in 1986, LISTSERV@BITNIC was enhanced to provide automatic list management, but this enhancement was abandoned a few months later when Bitnic installed Thomas' LISTSERV.
Other than their name, Bitnic's and Thomas' products are unrelated and neither product is based on the other product's code.
Though electronic mailing lists are not as popular as they once were, they survive due to their ease of use.