If you want to register a domain to make certain that nobody else will take it, however, you haven't built the site for it yet, you could park it. This is a service that registrar companies offer if a domain isn't connected to any web or email hosting service. That way, you can protect a brand name, for instance, and you will own the domain name in question even though it won't load any content. If you want, you may choose some default template that the registrar provides, such as For Sale or Under Construction, or you can forward the domain name to a new web address. The second option is very useful in case you own a few domain names, but you want each and every one of them to open the same website. As an example, you can register domain.net and domain.org, then park them and forward them to domain.com. In this example, you will need hosting for the third domain only and the traffic to the other ones is going to be redirected to it.