Oops! This page requires JS.
The green square is a link defined by the map. Clicking on the rest of the image submits x and y coordinates. This is an example showing that http://wheresmysquare.com/ could be done without using <input usemap> and without defining an area element for every spot on the image. Whether that site or this example uses <input usemap> properly and is accessible is another topic. This example should work in Opera, Firefox, Safari and IE.