Registering a domain name and hosting one is often mistaken by many people to be the same thing. They are in reality two separate services - the domain name registration is the actual name and nothing else, while the hosted domains feature refers to the number of already registered domain addresses which you could accommodate in the same hosting account and have website files and emails for them. Your sites will work in exactly the same way no matter whether the domain addresses are registered and hosted at the same place or are registered with company A and pointed to company B. Simply registering a domain address without hosting it will grant you ownership, but will not enable you to have a web site until you host this domain in some account so that records for it are set up and it starts opening the content from that account.