From the Conceptual dept.:
Today we are open-sourcing the project as Chromium OS. We are doing this early, a year before Google Chrome OS will be ready for users, because we are eager to engage with partners, the open source community and developers. As with the Google Chrome browser, development will be done in the open from this point on. This means the code is free, accessible to anyone and open for contributions. The Chromium OS project includes our current code base, user interface experiments and some initial designs for ongoing development. This is the initial sketch and we will color it in over the course of the next year.

We want to take this opportunity to explain why we're excited about the project and how it is a fundamentally different model of computing.

First, it's all about the web. All apps are web apps. The entire experience takes place within the browser and there are no conventional desktop applications. This means users do not have to deal with installing, managing and updating programs.

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