If you wish to point a domain address that you have to another domain or subdomain, one way to do that would be to use a CNAME record. By setting up such a record, the domain address being forwarded loses all its records (A, MX, etc) and instead, it takes the A record of the domain it is redirected to. In this way, if you use a web design service by some provider that gives you a subdomain, you can use an actual domain and not only will it be pointed to the website that you have set up, but it'll also be displayed in the web browser address bar at all times. Alternative possible uses of a CNAME record are to point all of the targeted traffic from different subdomains to their main domain name, or to use the webmail service of your webhosting company by using webmail.your-doman.com, for example. The latter will work only by setting up a CNAME record for a subdomain due to the fact that this kind of a record created for the main domain address makes it impossible to use e-mail addresses.