There are two services you need for a working site - a domain plus a web hosting plan for it. Whenever you type the domain address in your web browser, you see the content that’s uploaded inside the web hosting account, but if that domain isn't linked to such an account or to an email service, it is parked. To put it differently, the domain address is registered and you are its owner, but it doesn't have any content of its own. Instead, it can open either a pre-made “Under Construction / For Sale” Internet page from the registrar company, or it may be forwarded to some other URL of your choice. The main benefit of parking a domain name is that you can keep it and be sure that no one else is going to take it. Meanwhile, it will not take a slot for a hosted domain address inside your account. You may also park domains if you have a .com, for instance, and you register domain names with other extensions such as .net, .org or country-code ones to forward them to the main web site in order to protect a brand name.