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