There are two services that you need for a functioning web site - a domain name and a hosting plan for it. Each time you type the domain name in your web browser, you see the content that is uploaded in the website hosting account, but if that domain name isn't linked to such an account or to an email service, it's 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 can be forwarded to some other URL of your choice. The main advantage of parking a domain name is that you can keep it and ensure that nobody else is going to take it. Meanwhile, it will not block a slot for a hosted domain in your account. In addition, you can park domain names if you have a .com, for instance, and you register domain addresses with other extensions like .net, .org or country-code ones to forward them to the main site so as to protect a brand name.