If you wish to register a domain name to ensure that nobody else is going to take it, however, you have not created the site for it yet, you could park it. This is a feature that registrar companies offer when a domain isn't linked to any web or email hosting service. In this way, you'll be able to protect a brand name, for instance, and you will own the domain in question even though it will not open any content. If you want, you can select some default template that the registrar provides, like For Sale or Under Construction, or you can direct the domain to a different web address. Your second option is very useful if you own a number of domain names, but you want each and every one of them to open the same website. As an illustration, you could register domain.net and domain.org, then park them and direct 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.