There are two separate services you need for a functioning website - a domain and a website 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 isn't linked to such an account or to an e-mail service, it is parked. Put simply, the domain name 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” webpage from the registrar company, or it can be forwarded to any other URL of your choice. The main advantage of parking a domain is that you can keep it and make certain that no one else will take it. In the meantime, it will not take a slot for a hosted domain address in your account. You could also park domains if you have a .com, for example, and you register domain addresses with other extensions like .net, .org or country-code ones to direct them to the main website in order to protect a brand name.