LISTSERV

LISTSERV was the first electronic mailing list software application, consisting of a set of email addresses for a group in which the sender can send one email and it will reach a variety of people.^[1] Since its launch in 1986, several other list management tools have been developed, such as Lyris ListManager in 1997, Sympa in 1997, GNU Mailman in 1998.
Prior to LISTSERV, email lists were managed manually. To join or leave a list, people would write to the human list administrator and ask to be added or removed, a process that only got more time-consuming as discussion lists grew in popularity.
LISTSERV was freeware from 1986 through 1993 and is now a commercial product developed by L-Soft, a company founded by LISTSERV author Eric Thomas in 1994.^[2] A free version limited to ten lists of up to 500 subscribers each can be downloaded from the company’s web site.
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lsoft.com/download/listserv.asp