The hosted domains feature of a website hosting account indicates the number of registered domains that one could add within the very same account. Registering a domain and hosting it are two different services although some people consider them to be the very same thing. While the registration means you become the owner of a given domain address, the hosting part is what really enables you to have a website since this is where your files and e-mails are going to be. Since these are two different services, you are able to register a new domain address with one company and host it with another one by changing its name servers (DNS) - the domain is going to work in the exact same way just as if it was registered and hosted with the same company. Also, it is important to know that changing the hosting means directing the domain to a different company and not transferring it.