When you have several domain names with different extensions and you want all of them to open the exact same site, you can have the website under one of them and redirect the others. There are different approaches to forward one Internet domain name to another, such as the so-called domain parking. When your web hosting package allows it, though, it shall be better if you host all the domains and create 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, and so forth., while with a parked domain you can't do any of those things. As an example, if you're building localized websites under different country-code Internet domain names, you will be able to work on them, but in the meantime, people shall be forwarded to the main site.