Creating a CNAME record for any of the domain addresses or subdomains that you've got within a hosting account will permit you to redirect it to a different domain/subdomain. The forwarded domain will lose all of its records - A, MX etc, and will take the records of the domain name it's being directed to. In this light, you cannot create a CNAME record to direct your domain to a third-party company and keep a functional e-mail service with the first hosting company. Also, it is very important to know that a CNAME record is always a string of words rather than a number because it is generally wrongly identified as the A record of the domain being redirected. One of the primary uses of a CNAME record is to forward a domain address that you own through one company to the servers of some other company when you have created an Internet site with the latter. That way, the website will appear under your own domain address, not under some subdomain provided by the third-party company.