URL forwarding is just like it sounds. It is a service offered FREE by most domain registars.

Let's say you own the website www.widgets-r-us.com, and you register www.widgets-r-us.net as an alternative address to your website.

Rather than maintaining two copies of your website (one at each domain address) you can have the second domain "forwarded" to the primary domain. In other words, if somebody visits www.widgets-r-us.net, they will be automatically "forwarded" to www.widgets-r-us.com

Unmasked Forwarding reveals the URL which the visitor has been forwarded to. In other words, if somebody types www.widgets-r-us.net into their address bar and is automatically forwarded to www.widgets-r-us.com, the URL address bar will suddenly "change" to www.widgets-r-us.com.

Masked Forwarding simply means that the forwarding URL remains in the browser's address bar. In other words, if somebody types www.widgets-r-us.net into their address bar and is automatically forwarded to www.widgets-r-us.com, www.widgets-r-us.net will remain in their browser address bar.

Masked Forwarding is best when your website is being hosted on somebody else's domain. In other words, let's say your website URL is something like www.geocities.com/~gnrfreak82740 and you register www.widget-r-us.com to be forwarded to that address. It would look more "professional" to have remain in the browser address bar www.widget-r-us.com than www.geocities.com/~gnrfreak82740 !

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What is E-mail Forwarding?
Just like forwarding your postal mail