If you have several domain names with different extensions and you want all of them to open the exact same website, you can have the Internet site under one of them and forward the others. There are a number of approaches to forward one domain name to another, among them the so-called domain parking. If your hosting package permits it, though, it will be better if you host all the domains and set up a URL redirect, not a domain redirect. The real difference between the two is that while a domain name is hosted, you may still have content for it, create subdomains, e mail addresses, etc., while with a parked domain you can't do any of these things. As an example, if you're building localized websites under different country-code domain names, you shall be able to work on them, but in the meantime, people will be forwarded to the primary website.