An e-mail alias is an e-mail that shares a mailbox with a completely different email address. For instance, you could have firstname.lastname@example.org and email@example.com and messages sent to both of them will be received in one mailbox. This option will make it simpler and more convenient to handle a variety of email addresses because you will have to log into only one mailbox if you work with webmail or set up one e-mail address in an e-mail app on your PC. When you create an alias, not only will you be able to receive messages, but you'll also be able to send e-mails from the different addresses and they will share the Outbox, so you will still have all communication in a single place. Working with aliases is surely a replacement for using various email addresses for a variety of purposes or forwarding one address to a different one so that you can handle the emails of both in one place.