An email alias is an e-mail address that shares a mailbox with a totally different email. For instance, you could have info@domain.com as well as support@domain.com and messages sent to either one of them will be received in one and the same mailbox. This option will make it a lot easier and much more convenient to manage various email addresses because you will have to log in to one single mailbox if you use webmail as well as configure only one e-mail address in an e-mail client on your computer. When you set up an alias, you won't just have the ability to receive emails, but you will also be able to send out messages from the different addresses and they will share the Outbox, so you'll still have all communication in one location. Making use of aliases is a substitute for making use of different mailboxes for various purposes or forwarding one e-mail address to a new one to be able to handle the communication of both in one location.
