A third-party cookie is a small data packet that is created by a domain other than the one you are currently visiting. These cookies are often used for tracking and advertising purposes across multiple websites. Third-party cookies can be used to collect information about your browsing history, interests, and other personal data that can be used to deliver targeted ads or content.
For example, if you visit a website that has third-party cookies enabled, the cookie will be stored on your device by the third-party domain. This cookie can then be accessed by other websites that use the same third-party domain to track your activity across multiple sites. This is how advertisers can show you ads for products or services that you have previously searched for or viewed online.