A parked Internet domain is one which is taken, however it's not linked to another service - web or email hosting. To put it differently, this type of domain address will not load any actual content when you type it in a web browser, but nobody can take it as you've already registered it and you are its owner. The benefit of obtaining a domain name and parking it afterwards is that you will be able to keep it and not worry that someone else could possibly register it meanwhile if, for instance, the website for it is not ready yet. You could set a temporary Under Construction page for a parked domain name while you're working on the web site, or direct it to another web address - temporarily or permanently. The second option can be used when you have already registered domain.com, for example, and you obtain domain.net and domain.org, so as to protect a brand name or a trademark. In such a case, the .net and .org domain names can be parked and forwarded to the .com because you do not need different websites for them.