The hosted domains feature of a website hosting account indicates the amount of registered domain names which you could add in the very same account. Registering a domain name and hosting it are two different services although a lot of people consider them to be the same thing. While the registration signifies that you become the owner of a specific domain address, the hosting part is what in fact allows you to have a web site since this is where your files and e-mails will be. As these are two independent services, it is possible to register a new domain name with one company and host it with another by modifying its name servers (DNS) - the domain shall work in the exact same way just as if it was registered and hosted with the exact same company. It's also very important to know that changing the hosting means pointing the domain name to another company and not transferring it.