If you'd like to direct a domain address that you have to some other domain or subdomain, a good way to do this would be to use a CNAME record. By setting up such a record, the domain address being pointed loses all its records (A, MX, etc) and instead, it takes the A record of the domain it's directed to. That way, if you are using a web design service by some provider that gives you a subdomain, you can use an actual domain and not only will it be directed to the site that you have created, but it'll also be displayed in the browser address bar at all times. Alternative possible uses of a CNAME record are to direct all of the visitors from different subdomains to their main Internet domain, 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 created for the main domain name makes it impossible to use e-mail addresses.