A digital identity is data stored on computer systems relating to an individual, organization, application, or device. For individuals, it involves the collection of personal data that is essential for facilitating automated access to digital services, confirming one's identity on the internet, and allowing digital systems to manage interactions between different parties. It is a component of a person's social identity in the digital realm, often referred to as their online identity.
Digital identities are composed of the full range of data produced by a person's activities on the internet, which may include usernames and passwords, search histories, dates of birth, social security numbers, and records of online purchases. When such personal information is accessible in the public domain, it can be used by others to piece together a person's offline identity. Furthermore, this information can be compiled to construct a "data double"—a comprehensive profile created from a person's scattered digital footprints across various platforms. These profiles are instrumental in enabling personalized experiences on the internet and within different digital services.