There are several ways to direct a domain name to another domain or subdomain and one of them is by setting up a CNAME record. If you own a domain and you have set up a website through some on-line service which provides you with a service subdomain, you could easily link the two by creating a CNAME record for your-domain.com that points to subdomain.provider.com. What you will achieve with this is that www.your-domain.com is going to be in the browser address bar while it opens the already mentioned website from the servers of the third-party company. It is important to know that if you set up a CNAME record, any other records your domain may have will stop functioning, so you can't have both a CNAME record directing to one company and working email addresses with a different one. The CNAME record is always an alpha string, not a number, and in some cases more configuration may be needed with the other provider.