IBA Opt-out (by Google) is a Chrome extension that allows users to opt out of Google's interest-based ads while browsing the web. By installing this extension, users can prevent Google from showing them personalized ads based on their browsing habits.

One of the main features of IBA Opt-out is its ability to disable the DoubleClick advertising cookie, which is used by Google to display interest-based ads on partner websites. By opting out of this cookie, users can avoid seeing targeted ads on websites that collaborate with Google.

Another advantage of IBA Opt-out is that it stops interest-based ads on some of the websites that partner with Google. This ensures a more private and personalized browsing experience for users who prefer not to have their online activities tracked for advertising purposes.

IBA Opt-out is a one-time install on Chrome, meaning users only need to install the extension once to enjoy its benefits. Even if users clear their browser's cookies, the opt-out setting remains in effect, ensuring continued protection against interest-based ads.

For developers interested in the inner workings of IBA Opt-out, the extension is available as open source on the Google Code repository.

Please note that by using IBA Opt-out, users agree to the Terms of Service outlined in the extension's gallery page on the Chrome Web Store.