Rob Eberhardt

There's been a massive amount of cool software and web development lately involving maps.  I just want to nail down what I've seen in one place.  I'll try it as a timeline...

• For ages there were the "classic web" map websites, which reloaded the entire page for every zoom, pan or other change.  MapQuest was one of the first (what, 10 years ago?), and has changed little since then.  In a word, "slooow".
• Eventually some sites like Yahoo Maps and MSN Maps evolved some, using DHTML to dynamically swap the map image, without reloading the entire page.  This was definitely faster.
• More recently, there was Google Maps, which actually slices the map into separate map "tiles", so that only the changed parts of the map are downloaded for each zoom/pan/etc (which is even faster).  Definingly-cool features include satellite maps, and the ability to "grab/drop" to move the map with your mouse just like you'd grab and move a real one.  This also put AJAX (aka "Remote Scripting") on the buzz map as a web development technique.
  
  Update: Don't miss the many amazing "remixes" of Google maps with other web apps, like phone books, housing ads, and crime stats).  Just Wow.
• Then NASA released World Wind, a desktop application which does this same trick, but leverages DirectX to provide seamless zooming/panning -- a true 3D app, and very cool.  It's mouse-enabled much like Google Maps, but adds UI features like Tilting (which gives panning the sensation of a fly-over!) The focus is more educational/scientific reference than convenience (sorry, no driving directions to Wal-mart.)
• Google Earth is the most recent, which is basically a combination of Google Maps with World Wind.  Its UI features are very similar to World Wind's, but it has more practical user features like Google Maps (how about Flying directions to Wal-Mart!).  (It also has some business features like demographic information overlays and the like, which puts it in the arena of Microsoft's commercial MapPoint software).
• Update: A9 Maps is a new one.  It's a different interface, and sports "curb-view" photos of addresses.  ...Or says it does anyway, I can't find any around me, so I'm not sure what use that is.

All of these are free, by the way.

If you dig this kind of map stuff and/or astronomy, I recommend Celestia, a free 3D desktop app (like World Wind and Google Earth) for extra-terrestrial (as in "off Earth") virtual exploration.  It's a great reference and learning/teaching tool, and my 5yr old and I love it.