There are 2 services you need for a functioning web site - a domain name and a web hosting plan for it. If you type the Internet domain in your web browser, you see the content that is uploaded in the hosting account, but if that domain is not linked to such an account or to an e-mail service, it is parked. In other words, the domain name is registered and you are its owner, but it doesn't have any content of its own. As a substitute, it can open either a pre-made “Under Construction / For Sale” page from the registrar company, or it could be directed to some other URL of your choice. The main advantage of parking a domain address is that you can keep it and be sure that nobody else is going to take it. In the meantime, it will not occupy a slot for a hosted domain inside your account. You may 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 web site so as to protect a brand name.