Offline access to Web applications is becoming an important trend, with Adobe and Google looking to make the most of this new direction.

Representatives of the two companies touted offline access technologies during a presentation at the Web 2.0 Expo conference in San Francisco on Wednesday. Adobe provides its Adobe AIR (Adobe Integrated Runtime) software for this space, while Google is working on its Google Gears technology.

"Really, what it's about is developer choice," said Ryan Stewart, Adobe platform evangelist. Previously, the Web was limited to the browser, but now it is expanding, Stewart said. He cited several examples of new trends in Web technologies, including Prism, that bring Web applications to the desktop in a similar manner to Adobe.

"The creativity for development pretty much went to the browser," because it was cross-platform and easy to develop for, Stewart said. The browser helped foster development of exciting applications.

"Adobe AIR wants to bring some of that to the desktop," said Stewart. The company wants to take the best of the Web and offer more functionality beyond browser limitations, he said.

AIR users can take advantage of resources on their local machine; also, AJAX (Asynchronous JavaScript and XML) applications can be built inside AIR, Stewart said. AIR applications feature an installer supported across multiple operating systems. AIR provides real desktop applications that use Web technologies, and it features Flash integration and local file access.

"You really have full control over the file system," Stewart said.

Google's Dion Almaer hailed Google Gears, a beta-phase project intended to enable more powerful Web applications. Among other capabilities, Gears allows Web applications to interact naturally with the desktop.

Gears, Almaer said, is an open source update mechanism for the Web. Possible additions to Gears include a location API, providing the ability to know where a user of a browser is; an audio API; and a notification API, which would provide alerts for users.

Google Gears features a local server cache for application resources, the SQLite database for data storage, and the ability to make Web applications more responsive through the WorkerPool capability. Resource-intensive operations are performed asynchronously via JavaScript-based WorkerPool.

Almaer cited a user site, Buxfer, which is a Web 2.0 startup that handles personal finances for students sharing resources. Some users do not want to store their banking information in Buxfer servers; with Gears they can store it locally, said Almaer.

"They're using the database not in an offline [capacity] but just as a place to store this data," he said.

Gears was described as a bleeding-edge implementation of HTML 5, the specification for which features capabilities to help Web application authors and improved interoperability for user agents, according to the World Wide Web Consortium's Web page on HTML 5.