If you would like to direct a domain address that you have to another domain or subdomain, the best way to do this would be to use a CNAME record. By setting up such a record, the domain being forwarded loses all its records (A, MX, etc) and instead, it takes the A record of the domain it's redirected to. 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 directed to the website which you have created, but it will also be displayed in the browser address bar at all times. Other possible uses of a CNAME record are to forward all of the visitors from different subdomains to their main domain address, or to use the webmail service of your hosting company by using webmail.your-doman.com, for example. The latter will work only by setting up a CNAME record for a subdomain simply because such a record created for the main domain makes it impossible to use e-mail addresses.