An e-mail forwarding alias is an e-mail address that simply forwards mail to another address. The other address can be a POP mailbox on our servers or a mailbox on another server.
For example, if your domain name is example.com, you could set up an extra e-mail address named sales@example.com that forwards mail to both robert@example.com and example@aol.com.
These types of addresses are called "aliases" because they don't really provide new, separate mailboxes: instead, they provide extra custom addresses that forward mail to one or more real mailboxes elsewhere.
To create a forwarding alias: