Mailing lists are a way of leading structured threaded discussions with a larger number of participants over e-mail. The main advantages of mailing lists compared to sending messages to a list of participants via CC is that the sender of the message does not need to care about the individual participants, only about the group of people she wants to reach.

The general mode of operation for mailing lists is that a knowledge worker subscribes to a mailing list and will then receive all mails that are sent to the mailing list and will be able to send e-mails to the mailing list itself, thus reaching all other subscribers.

As an alternative for mailing lists, depending on the user group and the concrete use case, chat rooms and online forums and well as news groups have emerged.

Advantages of Mailing Lists compared to Online Forums

• All message processing happens in the knowledge worker's inbox, power users can apply rules to filter incoming mailing list messages
• Push-mode means that the knowledge worker does not need to visit a website regularily to get important updates
• Ideally suited for power users like the team communicator
  

Disadvantages of Mailing Lists compared to Online Forums

• Higher barrier of entry, as a subscription is needed
• No way of selective reading and commenting of messages or threads
• High volume of some mailing lists can obstract occassional readers
• Online forums have interactive archives, past discussions can be linked to
• Online forums have better search support

The Mindquarry Collaboration Server combines mailing lists and discussion forums. Occassional users can use it like a online forum or subscribe to particular threads and use it like a low-volume mailing list. Power users can subscribe to all threads, yet still have a searchable and linkable online archive.

Advantages of Mailing Lists compared to Chat Rooms

• Threaded discussions
• Allows for asynchronous communication
• Better archiving support
• Allows for higher number of participants before mailing list becomes too crowded
  

Disadvantages of Mailing Lists compared to Chat Rooms

• No real-time communication
• Longer response cycles