Email forwarders can be used with or without a POP email account.
When used without an email account, a forwarder can be set up like so:
sales@yourdomain.com --> bob@yourdomain.com
In this case, mail sent to sales@yourdomain.com is delivered to Bob's email account, even though the sales@yourdomain.com account doesn't exist on the server.
If there is an account for sales@yourdmain.com, the email is delivered to this address as well as being forwarded to bob@yourdomain.com.
Multiple forwarders can also be set up if required e.g. forwarding a generic email account to two or more people.
