Google maps using Javascript, XML, XSLT, and CSS to create a web application that behaves more like a desktop application. With normal web programming, the user is presented with a form, the user inputs data, the user submits the form, and finally the entire web page reloads with new content. AJAX, as this type of programming has been coined, does not require the reloading of the entire interface. The Javascript is able to make calls back to the server to get the required information and update only those parts of the interface that needs to change.Learning how to do things with the combination of technologies now known as AJAX seems like it would be super useful. But it's probably not easy if you don't already have programming knowledge, I would guess.
In the case of gCensus, every time the map is panned or zoomed the Javascript contacts the gCensus server and requests information for the viewable map region. At the same time, the Google code contacts the Google servers and requests the required images needed to display the map. The page is only reloaded when the user clicks the refresh button.
posted by cali at 10:40 AM on June 21, 2005