Google Chrome yesterday began a phased rollout of its changes to cookie tracking, with the launch of Chrome Tracking Protection, which restricts third-party cookies by default, began rolling out to 1% of Chrome users globally.
Third-party cookies are small pieces of data that are stored on a user's device by websites they visit. These cookies can be used to track a user's browsing activity across different websites, which can be used for advertising purposes.
Google will eventually replace third-party cookies with a new approach based on privacy-preserving APIs. Google plans to phase out third-party cookies entirely by the second half of 2024.
The phasing out of third-party cookies will make it more difficult for advertisers to track users across different websites. This could lead to a decrease in the effectiveness of targeted advertising.
Google is not the only browser that is phasing out third-party cookies. Firefox and Safari have already begun to do so.
Safari has been gradually phasing out third-party cookies since 2017. In 2023, Apple announced that it would completely disable third-party cookies in Safari by default in macOS Monterey and iOS 15. This change has already made it more difficult for advertisers to track users across different websites in Safari.