All of the code in this month's column was written using a combination of JavaScript and XHTML. If you are unfamiliar with JavaScript, you might want to look at David Flanagan's JavaScript: The Definitiv e Guide, published by O'Reilly. The XHTML is surprisingly readable an d includes many comments and examples of use to developers. You can read it at www.w3.org/TR/xhtml1 [1].

For more information about Google Maps, refer to the Google Maps API site at www.google.com/apis/maps [2]. You also will need to go to that site to get a key, if you decide to sign up for the service.

A short book on the subject, called Pragmatic Google Maps, was written by Scott Davis and published by the Pragmatic Programmers (pragmaticprogrammers.com [3]). It contains a lot of good advice for working with Google Maps and puts much of the API documentation into perspective.

The home page for Amazon Web Services (AWS) is www.amazon.com/gp/browse.html?node=3435361 [4]. From that page, you can register for an ID, download and read documentation (including code examples in a variety of languages), and participate in forums for AWS developers. A frequently updated Weblog with news and ideas about AWS is at aws.typepad.com [5].

All of Amazon's Web services can be accessed using either SOAP or REST. An overall introduction to SOAP, including XML examples, is at www.intertwingly.net/stories/2002/03/16/aGentleIntroductionToSoap.html [6].

The two geocoders mentioned in this column are geocoder.us (geocoder.us [7]) and Brainoff's geocoder (brainoff.com/geocoder [8]), both of which are mentioned in Pragmatic Google Maps.