The hosted domains feature of a web hosting account indicates the amount of registered domains that one can include in the exact same account. Registering a domain name and hosting it are 2 totally different services although a lot of people consider them to be the very same thing. While the registration means that you become the owner of a given domain name, the hosting part is what actually permits you to have a site as this is where your data and e-mails will be. As these are two different services, it is possible to register a new domain address with one company and host it with another one by changing its name servers (DNS) - the domain name shall work in the exact same way just as if it was registered and hosted with the same company. It is also important to know that changing the hosting means pointing the domain name to an alternative company and not transferring it.