A Catchall lets you capture all e-mails destined for non-existing users and redirect them to the mailbox of your choice.

Lists allow you to create distribution groups of users within your organization. You can also fine-tune the list settings, such as defining who can post to the list or the distribution method. 

E-mails sent to the list can be distributed to everyone simultaneously or in a roud-robin fashion. This is highly useful for sales departments that want to equally distribute incoming leads for example.

Aliases enable you to create valid e-mail addresses that forward to a real mailbox on the server or remotely.