There are two major types of LIstServ services

Discussion ListServ:

A Discussion ListServ is set up for a group of people that want to share ideas. Only members of the Discussion ListServ can send messages to the list and Only members can receive messages from the Discussion ListServ

Alert ListServ:

An Alert ListServ is set up for a group of people that want to receive messages from the owner of the ListServ. Only the owner of an Alert ListServ can send messages to the list and Only members can receive messages from the Alert ListServ

Options:

Both ListServ types have options that can be set up, they include:

• Digest Delivery
  about once a day delivery set by the user
  
• Regular Delivery
  messages sent to the user as sent to the ListServ, this option is set by the user
  
• Load Users
  This allows the owner to upload the e-mail addresses of the users
  
• Sign Up
  This allows people to sign up or subscribe to the ListServ, this option is activated by the owner of the ListServ.
  
• Owner Approval Required
  This allows the owner of the ListServ to restrict who is approved to be on the list or not. Owner Approve is an option selected by the owner. When not selected, people can simply subscribe without the approval of the owner.
  
• History (Beta)
  This is in test mode and not part of any plan. It allows users to search the history. We suggest setting up an email address and adding it to your list to store your history