A sandbox is security mechanism used to run an application in a restricted environment. 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. Even though the sandbox in Google Chrome uses some of the new security features on Windows Vista, it is fully compatible with Windows XP. Google Chrome’s multi process architecture allows for a lot of flexibility in the way we do security. We expect to work in the near future with the plug-in vendors to securely sandbox them as well.”]
Source: https://blog.chromium.org/2008/10/new-approach-to-browser-security-google.html