If you have a few domains with different extensions and you need all of them to open exactly the same Internet site, you could have the site under one of them and forward all the rest. There are a number of approaches to redirect one domain name to another, such as the so-called domain parking. If your hosting plan allows it, though, it'll be better if you host all of the domains and create a URL redirect, not a domain redirect. The main difference between the two is that while a domain is hosted, you could still have content for it, create subdomains, e mail addresses, and so on., while with a parked domain you cannot do any of these things. For instance, if you are building localized Internet sites under various country-code domain names, you'll be able to work on them, but meanwhile, people will be forwarded to the primary Internet site.