The three pillars that are used to capture information for the release are personas and channels, data and interfaces, and micro journeys. Personas and channels define who uses the application and how they access it. Data and interfaces define what information is stored and displayed in the application. Micro journeys define how users achieve their goals and outcomes in the application. Reference: https://academy.pega.com/library/81/pega-certified-business-architect-pcba-81