Can someone tell me what this effect is?

This may be simple..I just want to know what this effect is..below is the link..its where you put the mouse over a shadow and a person's image comes up (or in this case, vice versa)
I just want to know what its called, and can you do it in photoshop?
thanks in advance..

http://igotfreestyle.com/migente/iamnothing/iamnothing.html

The blackening effect of the image is just a silhouette.

What makes the image change when you put your mouse over it though, is called a "mouseover". It is accomplished with Javascript. You may be able to do it in ImageReady, but I am not positive. Any html editor program like Dreamweaver would allow you to do it pretty easily though.

THANKS! I'm off to research..

any got any tutorials on something like this would be much appreciated..

yeah you can do it with image ready

Its called as deker said 'mouseover' or 'a rollover.'

Simply put; there are 2 images that get swapped when the mouse is hovered over it - the easiest way to get that effect is to use Dreamweaver. First you obviously draw the 2 images u want to 'swap' via PS then using Dreamweaver you goto Insert and Select 'Interactive Image' RollOver, a new window comes up you then pick the first image then the second that the original will change into when the mouse is hovered over it.

You can get a trial (thats if u dont already have it) from cnet.com

and heres a tut that explains it in detail.

ROLLOVER IMAGES


good luck.

thanks to ALL of you!!