Enterprise architecture is a rigorous description of an organization's structure including components, relationships between components, and principles guiding the organization's design and evolution. It describes the terminology, composition of components, and relationships between the organization and external environment. Common frameworks for enterprise architecture include TOGAF, FEAF, DODAF, and Zachman, which differ in areas like customizability, technical documentation quality, and tool support. Enterprise architecture provides benefits like flexibility, aligning IT and business strategies, and reducing project risk.