When you have a few domains with different extensions and you would like all of them to open exactly the same site, you may have the website under one of them and forward all the rest. There are different ways to forward one Internet domain name to another, like the so-called domain parking. If your website hosting plan allows it, though, it'll be better if you host all the domains and create a URL redirect, not a domain redirect. The difference between the two is that while a domain address is hosted, you could still have content for it, create subdomains, e-mail addresses, and so on., while with a parked domain you are unable to do any of those things. As an example, if you are building localized websites under several country-code Internet domain names, you'll be able to work on them, but meanwhile, visitors shall be redirected to the primary site.