Tracking Cookies, and especially third-party tracking cookies, are commonly used as ways to compile long-term records of individuals’ browsing histories.
HTTP Cookies (also called web cookies, Internet cookies, browser cookies, or simply cookies) are small blocks of data created by a web server while a user is browsing a website and placed on the user’s computer or other device by the user’s web browser. Cookies are placed on the device used to access a website, and more than one cookie may be placed on a user’s device during a session.
Cookies serve useful and sometimes essential functions on the web. They enable web servers to store stateful information (such as items added in the shopping cart in an online store) on the user’s device or to track the user’s browsing activity (including clicking particular buttons, logging in, or recording which pages were visited in the past). They can also be used to save for subsequent use information that the user previously entered into form fields, such as names, addresses, passwords, and payment card numbers.
Authentication cookies are commonly used by web servers to authenticate that a user is logged in, and with which account they are logged in. Without the cookie, users would need to authenticate themselves by logging in on each page containing sensitive information that they wish to access. The security of an authentication cookie generally depends on the security of the issuing website and the user’s web browser, and on whether the cookie data is encrypted. Security vulnerabilities may allow a cookie’s data to be read by an attacker, used to gain access to user data, or used to gain access (with the user’s credentials) to the website to which the cookie belongs (see cross-site scripting and cross-site request forgery for examples).
—Wikipedia, “HTTP cookie”
First-Party Cookies are placed [on your computer] by the website you are visiting and are generally useful – they remember if you’re logged in or not, for example.
Third-Party Cookies are added to your device by other parties the website you’re visiting has made agreements with. Third-party cookies, which can be placed in ads, can track you as you move around the web. They build a profile of you by gathering data on your browsing history and linking it to an identifier that’s attached to your name.
This highly-personalised, intrusive, approach is then used to show you targeted adverts – that’s why that pair of jeans you looked at last week are now stalking you around the web, or why a shop can know you’re pregnant before you’ve told your family. But tracking people using third-party cookies has been going out of fashion for years: both Firefox and Safari have introduced blockers to actively stop them from working.
—WIRED, “Google’s cookie ban and FLoC, explained“
At some point next year, Google Chrome will stop using third-party cookies. It’s a move that could upend the global advertising and publishing industries – and it has major implications for your privacy.
Google’s cookie ban and FLoC, explained Read More