Registering a domain and hosting one is commonly mistaken by a lot of people to be one and the same thing. They are in reality two different services - the domain address registration is the actual name and nothing else, while the hosted domains feature reveals the number of already registered domain names that one could accommodate in the same web hosting account and have website data and emails for them. Your sites will function in precisely the same way no matter if the domain addresses are registered and hosted at the same place or are registered with company A and directed to company B. Simply registering a domain address without hosting it will grant you ownership, but will not allow 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.