No, it's not a medical condition it's a question. I'm not actually sure if it should be posted here or in the JS section or whatever as I'm not sure what technology will create the solution.

On my site I have four image thumbs running across the middle:

Now I don't want to reformat them or alter them in any way, but when clicked on I'd like each image to expand into a mini window within the main window - Just like when one clicks on an image in someones photo album on Facebook. It would also be good if I had the ability to add a caption. So just to be clear, I don't want it to open in a separate browser window or tab.

I'm using Dreamweaver at the moment but only to hand code HTML/CSS. I don't have any understanding of JS (yet).

Any advice will be gratefully received.