There are two separate services that you need for a functioning web site - a domain name plus a hosting plan for it. Each time you type the domain address in your Internet browser, you see the content that is uploaded inside the hosting account, but if that domain is not linked to such an account or to an e-mail service, it is parked. Put simply, the domain is registered and you are its owner, but it doesn't have any content of its own. Rather, it can open either a pre-made “Under Construction / For Sale” Internet page from the registrar company, or it may be directed to any other URL of your choice. The benefit of parking a domain address is that you can keep it and be sure that nobody else is going to take it. At the same time, it will not occupy a slot for a hosted domain address inside your account. You may also park domains if you have a .com, for instance, and you register domains with other extensions like .net, .org or country-code ones to direct them to the main web site so as to protect a brand name.