There are two separate services you'll need for a working website - a domain name plus a website hosting plan for it. Whenever you type the domain name in your web browser, you see the content that is uploaded within the web hosting account, but if that domain isn't linked to such an account or to an e-mail service, it's parked. To put it differently, the domain name is registered and you are its owner, but it doesn't 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 forwarded to any other URL of your choice. The main advantage of parking a domain address is that you can keep it and ensure that nobody else will take it. In the meantime, it won't occupy a slot for a hosted domain address in your account. You may also park domain names 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 site in order to protect a brand name.