If you want to register a domain to ensure that nobody else is going to take it, but you have not built the website for it yet, you may park it. This is a feature that registrar companies offer when a domain name is not connected to any web or e mail hosting service. This way, you'll be able to protect a brand name, for example, and you'll own the domain address in question although it won't open any content. If you want, you can pick some default template that the registrar offers, like For Sale or Under Construction, or you can forward the domain name to a different web address. Your second option is very helpful in case you own a number of domain names, but you want each and every one of them to open the same site. As an example, you may register domain.net and domain.org, then park them and forward them to domain.com. In this example, you are going to need hosting for the third domain address only and the traffic to the other ones is going to be redirected to it.