A parked domain name is one that is taken, but it's not connected to another service - web or e-mail hosting. To put it differently, this type of domain won't open any actual content in case you type it inside a browser, but nobody can take it as you've already registered it and you are its owner. The advantage of getting a domain name and parking it afterwards is the fact that you will be able to keep it and not stress that someone else might register it in the meantime if, for instance, the site for it is not ready yet. You are able to set a short-term Under Construction webpage for a parked domain while you are working on the website, or direct it to another web address - temporarily or permanently. The latter option can be used when you have already registered domain.com, for example, and you obtain domain.net and domain.org, so that you can protect a brand name or a trademark. In this case, the .net and .org domains can be parked and forwarded to the .com as you don't need different websites for them.