There are two separate services that you need for a working site - a domain name plus a hosting plan for it. When you type the domain address in your web browser, you see the content that’s uploaded inside the website hosting account, but if that domain isn't linked to such an account or to an e-mail service, it is parked. In other words, the domain address is registered and you're 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” Internet page from the registrar company, or it can be directed to any other URL of your choice. The benefit of parking a domain is that you can keep it and ensure that nobody else is going to take it. At the same time, it will not block a slot for a hosted domain inside your account. You may also park domains if you have a .com, for example, 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.