Thursday 31st May is the first ever Google Developer Day, with more than 5000 developers at 10 locations around the world taking part. Keynotes and breakout sessions will be taking place in Sydney, Tokyo, Beijing, Moscow, Sao Paulo, Madrid, Paris, Hamburg, London, and Mountain View, California. Both Google engineers and product managers will be on hand to discuss the future of web applications with developers from right around the globe.

The idea being that Google can articulate its strategy for working with the developer community while reinforcing its commitment to drive open standards for developers both inside and outside Google in order to create web applications quickly.

"One of the things we find most exciting about emerging web technologies is the ability to mash up many different pieces of technology to build new applications, create businesses, or even just satisfy that niche interest or convenience," Jeff Huber, vice president of engineering at Google told me. "We want to work closely with developers so together we can define the next generation of products available to users on the web."

During Developer Day, Google will share details and demos of a new open source technology for creating offline web applications. The new browser extension, named Google Gears, is being made available in its early stages to the developer community so that everyone can test its capabilities and limitations and help improve upon it. The long-term hope is that Google Gears can help the industry as a whole move toward a single standard for offline capabilities.

Google will also be releasing the Google Mashup Editor today, an experimental online code editor for building mashups using a simple markup language. Aimed at developers familiar with HTML and JavaScript, the Google Mashup Editor offers a simpler way to deploy AJAX user interface components atop existing feeds and Google web services. By substituting extended XHTML tags for entire blocks of JavaScript code and hosting the mashups on Google servers, the Google Mashup Editor speeds mashup creation and fosters more powerful, more interesting web applications. Also keep an eye open for Google Mapplets, an API for embedding third-party applications in Google Maps. Since the Google Mapplets API combines the Google Maps API and the Google Gadgets API, anyone familiar with those APIs can quickly build a Google Mapplet and reach millions of Google Maps users.

Not been invited? Never mind, the Google Developer Day website will provide live webcasts of the sessions from the Mountain View and London events. In addition, the website will offer blogs, schedules, presentations, Developer Day photos, and links to recorded videos from sessions around the world. Oh yes, and all session videos will also be available on a Google Developer Day channel on YouTube.