A total set of data left behind by a person using a digital system. A person’s digital foot print includes all information actively provided by that person such as interactions on social networks (for example, comments, photographs), online purchases, website logons, emails and instant messages. It also includes passive information such as logs of software installed and used on a computer, metadata associated with files, a user’s IP address, a device being used to access a web page, and a user’s browsing history stored as cookies or by internet service providers.