Most websites aggregate content from many sources, including embedding third party content that can introduces third party code to the website payload.
The embedded third party content can provide cookies.
By passing cookies on access to sites, and detecting if the user has a previously provided tracking cookie, a tracker can build up a profile of sites accessed by a user.
- Useful for predicting user behaviour
- Targeted advertising Some negatives include
- Repeated access to the same sites / echo chamber of similar content as suggestion engines use previous history