Registering a domain and hosting one is often mistaken by a lot of people to be one and the same thing. They're in reality two different services - the domain registration is the actual name and nothing more, while the hosted domains feature shows the number of already registered domain addresses which you could accommodate in the same web hosting account and have site files and emails for them. Your sites will work in exactly the same way no matter if the domain names are registered and hosted in one place or are registered with company A and pointed to company B. Simply registering a domain name without hosting it will give you ownership, but will not allow you to have a web site if you don't host this domain name in some account so that records for it are set up and it starts opening the data from that account.