There are numerous ways to direct a domain address to an alternative domain or subdomain and one of them is by creating a CNAME record. In case you own a domain name and you have created a website using some online service which supplies 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're going to achieve by doing this is that www.your-domain.com will be in the web browser address bar while it opens the already mentioned site from the servers of the third-party company. You should know that if you create a CNAME record, any other records your domain name may have will stop working, so you can't have both a CNAME record pointing to one provider and functioning email addresses with another. The CNAME record is always an alpha string, not a number, and in some cases more configuration may be needed with the other company.