There are two services you need for a working site - a domain plus a hosting plan for it. When you type the domain name in your web browser, you see the content that’s uploaded within the web hosting account, but if that domain address is not linked to such an account or to an e-mail service, it's parked. To put it differently, the domain address is registered and you're its owner, but it does not have any content of its own. Instead, it can open either a pre-made “Under Construction / For Sale” webpage from the registrar company, or it can be directed to any other URL of your choice. The advantage of parking a domain address is that you can keep it and make certain that no one else is going to take it. At the same time, it won't take a slot for a hosted domain name within your account. You can also park domain names if you have a .com, for example, and you register domain addresses with other extensions such as .net, .org or country-code ones to direct them to the main website as a way to protect a brand name.