1. What is an email alias?
An email alias is another name for your email account. It allows for different email addresses to share the same mailbox. It can be used to have mail for a given email address be sent to one or more different recipients. For example, if your email address is you@yourcompany.com and you would like your contacts to send mail to info@yourcompany.com, this can be done by adding "info" as an alias pointing to the your mailbox.
2. What does it mean to forward to an email address?
Forwarding to an email address is very similar to an alias for an email address. The difference is that if the two or more email addresses you want to check under one mailbox are in two or more different domains, you must 'forward' the mail from one email address to another email address.
3. Why do I need a new email address when I have one through my Internet Service Provider (ISP)?
If you change your ISP, you will lose your email address. If you had a personal email address and want to keep that one in addition to adding new email address, you may do this using aliases or mail forwarding.