The hosted domains feature of a hosting account denotes the amount of registered domain names which you can add within the very same account. Registering a domain and hosting it are 2 totally different services although a lot of people consider them to be the exact same thing. While the registration ensures that you become the owner of a given domain address, the hosting part is what really allows you to have a site as this is where your data and email messages will be. Because these are two independent services, you are able to register a new domain with one company and host it with another by changing its name servers (DNS) - the domain address is going to work in the exact same way just as if it was registered and hosted with the same company. It's also very important to know that changing the hosting means pointing the domain name to an alternative company and not transferring it.