Registering a domain name and hosting one is often mistaken by a lot of people to be the same thing. They are actually two separate services - the domain name registration is the actual name and nothing more, while the hosted domains feature shows the number of already registered domain names which you could accommodate within the same hosting account and have site data and emails for them. Your sites will work in precisely the same way regardless of whether the domains are registered and hosted in one place or are registered with company A and directed to company B. Simply registering a domain address without hosting it will give you ownership, but will not enable you to have a web site unless you host this domain address in some account so that records for it are created and it starts opening the content from that account.