The hosted domains feature of a hosting account refers to the amount of registered domains that you could add within the very same account. Registering a domain address and hosting it are 2 totally different services although some people consider them to be the very same thing. While the registration ensures that you become the owner of a certain domain address, the hosting aspect is what actually allows you to have a site since this is where your data and email messages are going to be. As these are 2 different services, you'll be able to register a new domain with one company and host it with another one by modifying its name servers (DNS) - the domain address is going to work in the exact same way as if it was registered and hosted with the same company. Additionally, it is important to know that changing the hosting means directing the domain name to another company and not transferring it.