Google, whose Google Maps captured the imagination of Web developers, is making the Ajax tools it used to produce Google Maps available for free download.

Google is announcing its Google Web Toolkit Wednesday at the JavaOne Conference in San Francisco.

The toolkit includes a compiler that takes Java code and compiles it in what many Java programmers would consider a reverse direction. Its output is JavaScript.

JavaScript is a scripting language that lacks many of the rules and disciplines of Java. But JavaScript is an element of Ajax, and developing with Ajax allows Web application builders to quickly implement client interfaces that are highly interactive with end users.

One drawback to Ajax that the Google toolkit will ease is the tendency of Ajax to show user interface elements in different ways in different browsers. Ajax consists of JavaScript working with dynamic HTML "but they are not ideal technologies due to subtle inconsistencies between Web browsers," says Bret Taylor, product manager for Google developer programs, in an interview. The Google Web Toolkit will help "get rid of Ajax headaches," he says.

The toolkit is available for download, along with more information about it.

"We developed a lot of Ajax expertise in developing Google Maps, Google Calendar and GMail," says Taylor. It's making the source code of its library of user interface components available as part of the free download. But the compiler and debugger will be available only as compiled or binary code so that they remain the intellectual property of Google.

The toolkit may be used to develop commercial applications for resale and for uses inside the enterprise, Taylor added. It's offered under an Apache 2.0 license, which allows commercial reuse of the code.