Tracker
Also known as: third-party tracker, tracking pixel
Code, pixel or request that collects information about a user across websites.
A tracker is any piece of code, image or network request whose purpose is to gather data about you, your device or your behaviour, usually for advertising, analytics or fraud detection.
Trackers can be obvious (a Facebook Like button, a Google Analytics script) or invisible (a 1×1 pixel image, a server-side conversion ping). Most modern trackers chain together: one script loads another, which sets a cookie, which feeds an ad auction.
Examples
- Google Analytics, Meta Pixel, TikTok Pixel, Hotjar, FullStory.
Related terms
Identifying a user by combining many small browser and device attributes into a unique signature.
A cookie set by a domain other than the one in the address bar, used to track users across sites.
An invisible image used to silently report a page view or event back to a tracker.