If you'd like to register a domain to make sure that nobody else will take it, but you haven't built the site for it yet, you can park it. That is a service that registrar companies offer if a domain is not linked to any web or e-mail hosting service. By doing this, you can protect a brand name, for example, and you will own the domain name in question even though it will not open any content. If you want, you can choose some default template that the registrar offers, such as For Sale or Under Construction, you can also forward the domain to an alternative web address. Your second option is very useful in case you own a few domains, but you want each and every one of them to open the same site. As an illustration, you may register domain.net and domain.org, then park them and direct them to domain.com. In this example, you're going to need hosting for the third domain name only and the traffic to the other ones will be redirected to it.