Building a secure browser is a top priority for the Chromium team; it's why we spend a lot of time and effort keeping our code secure. But as you can imagine, code perfection is something almost impossible to achieve for a project of this size and complexity. To make things worse, a browser spends most of its time handling and executing untrusted and potentially malicious input data. In the event that something goes wrong, the team has developed a sandbox to help thwart any exploit in two of the most popular vectors of attack against browsers: HTML Rendering and JavaScript execution.
In a nutshell, a sandbox is security mechanism used to run an application in a restricted environment. If an attacker is able to exploit the browser in a way that lets him run arbitrary code on the machine, the sandbox would help prevent this code from causing damage to the system. The sandbox would also help prevent this exploit from modifying and even reading your files or any information on the system.
We are very excited to be able to launch Google Chrome with the sandbox enabled on all the platforms we currently support. Even though the sandbox in Google Chrome uses some of the new security features on Windows Vista, it is fully compatible with Windows XP.
Linux users are some of the first to tout (or 
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