A digital footprint is the "trail" an Internet user leaves as a result of his or her online activity. A digital footprint is not the same as a digital identity, rather, its the metadata collected or stored when a user moves around the Internet. When enough data is pulled together, though, a digital footprint can strongly suggest a user's identity.
All actions online leave a trace, even if privacy settings on a particular website are set to "private" and geolocation is disabled. Cookies are the most frequently used method of capturing user data while the user is visiting a website. While tracking a user's digital footprints can be used for nefarious purposes, retailers and advertisers frequently tracks users' digital footprints to better understand their target markets and provider products and services that serve customers.
There are generally two kinds of data gathering that track user data: Passive and active. Passive tracking occurs largely without the user's knowledge or "in the background." Passive digital footprints may track the user's IP address, time of activity, or location. Active footprints are the result of the user sharing information on social media, in chat rooms or forums, through Web apps, etc. Passive data collection and a user's resultant digital footprint have raised questions about user privacy rights and data ownership.