Modular content framework and document format methods and systems are described. The described framework and format define a set of building blocks for composing, packaging, distributing, and rendering document-centered content. These building blocks define a platform-independent framework for document formats that enable software and hardware systems to generate, exchange, and display documents reliably and consistently. The framework and format have been designed in a flexible and extensible fashion. In addition to this general framework and format, a particular format, known as the reach package format, is defined using the general framework. The reach package format is a format for storing paginated documents. The contents of a reach package can be displayed or printed with full fidelity among devices and applications in a wide range of environments and across a wide range of scenarios.