Domain name registration (like a company name) are just the name, into for them to operate into a website, the domain must be appoint a nameserver (like company registered country). Then that nameserver will answer anyone in the world whom that domain ip address (like checking the company post address), where the host record of that domain name is like a department with in that company, example “sales”, “accounting”, “marketing”, “www”, etc. when there are type in to the web browser (Internet Explorer, Firefox) “sales.company.com”, “accounting.company.com
, “marketing.company.com”, “www.company.com”, etc.
Now for your domain provider is offer you 3 options,
1) You are just registering the domain name with them, and using the web hosting provider nameserver
2) You are registering the domain name with them, and that you are using their nameserver to answer the ip address of the website, usually you would a dedicate ip for your website (like SSL, VPS, Dedicate server)
3) You are registering the domain name with them, and when someone type in the domain of your website, it will redirect to your old but url. Example “www.superrich.com” (type in this) => “superrich.hi5.com” (it will change to this in the browser)
I hop this would help you understand domain name registration abit more.