There are two main classifications for digital footprints: passive and active. A passive digital footprint is created when data is collected without the owner knowing, where as active digital footprints are created when personal data is released deliberately by a user for the purpose of sharing information about oneself by means of websites or social media.
Passive digital footprints can be stored in many ways depending on the situation. In an online environment a footprint may be stored in an online data base as a "hit". This footprint may track the user IP address, when it was created, and where they came from; with the footprint later being analyzed. In an offline environment, a footprint may be stored in files, which can be accessed by administrators to view the actions performed on the machine, without being able to see who performed them.
Active digital footprints can also be stored in many ways depending on the situation. In an online environment, a footprint can be stored by a user being logged into a site when making a post or change, with the registered name being connected to the edit. In an off line environment a footprint may be stored in files, when the owner of the computer uses a keylogger, so logs can show the actions performed on the machine, and who performed them. One of the features of keylogger is to monitor the clipboard for any changes as the user will sometimes have a very good habit of copying and pasting passwords and taking screenshots.
Tony Fish expounded upon the possible dangers of digital footprints in a 2007 self-published book. The closed loop takes data from the open loop and provides this as a new data input. This new data determines what the user has reacted to, or how they have been influenced. The feedback then builds a digital footprint based on social data, and the controller of the social digital footprint data can determine how and why people purchase and behave.
On the World Wide Web, the internet footprint; also known as cyber shadow, electronic footprint, or digital shadow, is the information left behind as a result of a user's web-browsing and stored as cookies. The term usually applies to an individual person, but can also refer to a business, organization and corporation.
Information may be intentionally or unintentionally left behind by the user; with it being either passively or actively collected by other interested parties. Depending on the amount of information left behind, it may be simple for other parties to gather large amounts of information on that individual using simple search engines. Internet footprints are used by interested parties for several reasons; including cyber-vetting, where interviewers could research applicants based on their online activities. Internet footprints are also used by law enforcement agencies, to provide information that would be unavailable otherwise due to a lack of probable cause. In addition your digital footprint is being used by marketers in order to find what products a user may be interested in, or to inspire ones' interest in a certain product based on similar interests.