If you want to register a domain name to make certain that nobody else will take it, however, you haven't created the site for it yet, you may park it. That is a feature that registrar companies offer if a domain name isn't connected to any web or email hosting service. By doing this, you'll be able to protect a brand name, for instance, and you'll own the domain address in question although it won't open any content. If you want, you can choose some default template that the registrar offers, such as For Sale or Under Construction, alternatively you can direct the domain to an alternative web address. Your second option is very helpful if you own a few domains, but you want every one of them to open the same website. For instance, 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.