A parked domain is one that is taken, but it is not connected to any other service - web or e-mail hosting. Put simply, this kind of domain won't load any actual content when you type it inside an Internet browser, but no one else can take it as you've already registered it and you are its owner. The advantage of acquiring a domain name and parking it afterwards is the fact that you are able to keep it and not worry that somebody else might register it in the meantime if, for instance, the site for it is not ready yet. You could create a short-term Under Construction website page for a parked domain address while you're working on your web site, or direct it to another web address - temporarily or permanently. The latter option can be used if you have already registered domain.com, for example, and you get domain.net and domain.org, so that you can protect a brand name or a trademark. In such a case, the .net and .org domains can be parked and forwarded to the .com since you don't need separate sites for them.