An identity can be placed on a continuum where one end is the anonymous state and the other end is the known state. In the anonymous state, identity is defined by cookie, device ID, or other digital identity marker. Most of these fall into the category of personally identifiable information. Unfortunately for marketers, not all of these identity attributes identify a unique individual.
Instead they identify devices, or live in the silo of a platform without links between other attributes. This complexity is why identity graphs are constructed.
An identity graph consists of 3 main parts: Terrestrial, Device and Digital Identity. Each of these parts encompasses a specific set of identity attributes.
The terrestrial identity contains physical identity attributes such as name, address, phone number; and is intended to be a persistent identifier as someone changes addresses, phone numbers and even names.
Device identity identifies a specific device and Internet browser on that device. On its own, device identity cannot uniquely identify an individual. The most common device identifier is a cookie. While individual linkage to a device identifier can occur, it typically requires a login or form submission, to create this association.
The digital identity is the set of identity attributes that define an individual’s persona. These personas would encompass identities like Facebook user IDs, Twitter handles, forum avatars, or even login identities. Digital identities may change from platform to platform, but they are common across devices. Together, these parts make the anatomy of an identity.