If you wish to create a web site, you need two things - your own domain and a hosting plan for it. The domain registration is the actual web address which you type in a browser to reach a site, while the hosting space is where your website files will be. These are 2 tightly related, but separate services, while many people believe that registering the domain is enough. Much like the disk space and the monthly traffic features that a given website hosting plan provides, there are a certain number of registered domains you can add as hosted i.e. you can have the web content for them in some account even when the domains are actually registered through a different company. In technical terms, it doesn't matter if a domain name is registered and hosted with the exact same company or is registered with one company and pointed to another - in any case your sites will function in exactly the same way.