If you wish to register a domain to ensure that no one else is going to take it, but you have not built the website for it yet, you can park it. That is a service that registrar companies offer when a domain address isn't connected to any web or e-mail hosting service. By doing this, you can protect a brand name, for instance, and you will own the domain address in question although it won't load any content. If you would like, you can pick some default template that the registrar provides, such as For Sale or Under Construction, or you can direct the domain name to a new web address. Your second option is very helpful in case you own a number of domain names, but you want every one of them to open the same site. For instance, 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 address only and the traffic to the other ones will be redirected to it.