There are a number of ways to forward traffic from one domain/website to another. The so-called URL redirection is frequently recommended. In contrast to parking a domain name, a URL redirection is possible only if the domain in question is hosted. What this means basically is that you could still open any content if you have a direct link to it and you may set up email addresses or subdomains and use them. Such a feature has several practical uses - if you decide to switch your domain address, you may forward the visitors, but the emails with the old one shall still be active in case you are making contact with clients or partners. When you have two identical Internet sites and you need to rebuild one of them, you could redirect the website visitors to the other website so as to avoid losing potential clients, while you'll still be able to access the administration area for the first Internet site and work on it.