There are two services you need for a functioning website - a domain name plus a website hosting plan for it. When you type the Internet domain in your Internet browser, you see the content that is uploaded within the web hosting account, but if that domain is not linked to such an account or to an e-mail service, it is parked. To put it differently, the domain name is registered and you're its owner, but it lacks 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 some other URL of your choice. The advantage of parking a domain is that you can keep it and make sure that no one else is going to take it. At the same time, it will not take a slot for a hosted domain name inside your account. You can 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 forward them to the main website in order to protect a brand name.