The hosted domains feature of a web hosting account refers to the number of registered domains that you could add in the exact same account. Registering a domain and hosting it are two completely 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 actually permits you to have a website because this is where your files and e-mails will be. Since these are 2 independent services, you'll be able to register a new domain name with one company and host it with another one by changing 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. Also, it is extremely important to know that changing the hosting means pointing the domain name to an alternative company and not transferring it.