CEO Steve Ballmer that a technical preview of the new Office 365 -- the online version of the product -- is available now to download and test at www.office.com/preview. He said it's the first version of Office built from the ground up for online use, and called it "the most ambitious release of Office we've ever done."

There will also be a shrink-wrapped version, called Office 2013, but it was the online version that Microsoft emphasized Monday. The company demonstrated the new applications, including Word, PowerPoint, Excel, Outlook and OneNote, at a press event in San Francisco.

In each case the user interface appears cleaner, with far more white space than in previous versions, and the programs have been optimized for touch using fingers or a stylus. Many of the apps support pinch-to-zoom, for example, and documents can be moved around and off the screen with a fingertip.

The applications will also work well with a keyboard and mouse, according to Microsoft, though it didn't show that on Monday. The apps were all demonstrated on a Samsung tablet running the soon-to-be-released Windows 8 OS.

Word exemplifies some of the bigger changes. Upon opening the online version, the user first has to log in and then sees their recently used documents and templates. Because it's a cloud-based service, the new Word can remember what the user was doing when they last closed the program, regardless of what system they are using it on. The application can take them back to the point they left off typing in a document, for example.