A parked domain is one which is taken, however it's not connected to another service - web or email hosting. In other words, such a domain will not load any actual content when you type it inside a web browser, but nobody else can take it as you have already registered it and you are its owner. The benefit of getting a domain and parking it afterwards is that you will be able to keep it and not worry that somebody else may register it meanwhile if, for instance, the site for it is not ready yet. You are able to create a short-term Under Construction website page for a parked domain address while you are working on the web site, or forward it to some other web address - temporarily or permanently. The second option can be employed when you have already registered domain.com, for example, and you get domain.net and domain.org, in order to protect a brand name or a trademark. In such a case, the .net and .org domain addresses can be parked and forwarded to the .com as you do not need different websites for them.