There are 2 services you need for a functioning web site - a domain plus a website hosting plan for it. Each time you type the domain address in your web browser, you see the content that is uploaded within the web hosting account, but if that domain name is not linked to such an account or to an e-mail service, it is parked. To put it differently, the domain is registered and you're its owner, but it does not have any content of its own. Rather, it can open either a pre-made “Under Construction / For Sale” Internet page from the registrar company, or it could be directed to some other URL of your choice. The main benefit of parking a domain is that you can keep it and make sure that nobody else will take it. Meanwhile, it's not going to occupy a slot for a hosted Internet domain within your account. You can also park domains 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 site so as to protect a brand name.