Google’s release today of a test version of its new open-source web browser, Chrome, marks an important moment in the ongoing shift of personal computing from the PC hard drive to the Internet “cloud.” I distinctly remember when, back in 1988, Apple Computer added MultiFinder to its Macintosh operating system, allowing my beloved Mac Plus to run more than one application at a time. That was, for us Mac users, anyway, a very big deal. Chrome – if we can trust the comic book – promises a similar leap in the capacity of the cloud to run applications speedily, securely, and simultaneously. Indeed, it is the first browser built from the ground up with the idea of running applications rather than displaying pages. It takes the browser’s file-tab metaphor, a metaphor reflecting the old idea of the web as a collection of pages, and repurposes it for application multitasking. Chrome is the first cloud browser.

Though the initial beta release of Chrome runs only on Microsoft’s Windows operating system, Chrome is being seen as yet another sharp Google stick aimed at the Beast of Redmond’s cyclopean eye – an attempt not only to displace Internet Explorer but to disintermediate Windows itself as the platform of choice for running PC software. There is, no doubt, truth to that view, but in this case I think Google is motivated by something much larger than its congenital hatred of Microsoft. It knows that its future, both as a business and as an idea (and Google’s always been both), hinges on the continued rapid expansion of the usefulness of the Internet, which in turn hinges on the continued rapid expansion of the capabilities of web apps, which in turn hinges on rapid improvements in the workings of web browsers.

To Google, the browser has become a weak link in the cloud system – the needle’s eye through which the outputs of the company’s massive data centers usually have to pass to reach the user – and as a result the browser has to be rethought, revamped, retooled, modernized. Google can’t wait for Microsoft or Apple or the Mozilla Foundation to make the changes (the first has mixed feelings about promoting cloud apps, the second is more interested in hardware than in clouds, and the third, despite regular infusions of Google bucks, lacks resources), so Google is jump-starting the process with Chrome.

Although I’m sure Google would be thrilled if Chrome grabbed a sizable chunk of market share, winning a “browser war” is not its real goal. Its real goal, embedded in Chrome’s open-source code, is to upgrade the capabilities of all browsers so that they can better support (and eventually disappear behind) the applications. The browser may be the medium, but the applications are the message.