An e-mail alias is an email address that uses exactly the same mailbox along with the initial email address. For example, you could have firstname.lastname@example.org as your original address and add an alias email@example.com. Each of the addresses will be able to share exactly the same mailbox, so e-mails sent to either one of them will be received in a single place. You can use aliases for a number of reasons, for example communicating with numerous teams of people or registering on web sites. Any time you start getting a number of spam, for example, you can simply remove the alias whilst your actual mailbox will not be changed at all and you'll retain the emails you need. Aliases are often considered to be an alternative to forwarding e-mails from one mailbox to another if you work with more than one addresses for contact on your web site.