An email service in which individual members post messages for all group members to read (“many to many.”) In contrast, a newsletter is a “one to many” broadcast, where comments by members or subscribers go only to the message sender. Aka by the trademarked name Listserv.

Building Your Business with an Opt-in List
Before revealing the secrets of the trades, here are myths and fallacies that need to be cleared before one indulges into building an opt-in list.