Zmarties

Google Maps is a lot of fun, and once again pushes the boundaries of what we now expect can be achieved in a browser based application.

Its main features are:

• a map of the USA (and some of Canada) that can be dragged around, and zoomed into interactively, using mouse or keyboard
  
• the map sizes to fit your window, and all transitions happen without reloading the browser page
  
• local search results can be overlaid on the map
• you can calculate driving instructions between two point, and the route is also overlaid on the map

None of these features are unique, but the package is very neatly put together, and polished.

The underlying techniques used are varied, and there's a good introduction at Mapping Google. These include:

• CSS - the map is built up from a lot of individually positioned small 128 pixel square tiles, which get repositioned as you scroll around
  
• JavaScript - to hold it all together
• XML - processed client side, via XSL, especially used for the search results
  
• transparent png images - for pushpins, speech bubbles, and driving route overlays
• an IFrame - as a back button friendly alternative to XMLHTTPRequest
  

Other useful and informative information on Google Maps can be found at:

• Firefox searchbar for Google Maps
• Slashdot discussion on Mapping Google
• Google Maps and XSL
• Google maps and bookmarks
  

This beta only holds data for the USA. If you want to see a similarly featured, though ultimately less usable system that includes European data, check out Maps24 which provides an interactive map via the use of a Java applet. (Their zoom in from a continent wide view to street level is very impressive the first couple of times you see it!)

Also worth looking at this map of Switzerland that I've mentioned before.

Update: More very informative musings are at:

• Making the back button dance
• Still more fun with maps
• Google Maps Bookmarklets