The document introduces Object Process Methodology (OPM) as a holistic modeling methodology that uses a single model to represent both the structure and behavior of systems using object-process diagrams and an object-process language. It discusses key OPM concepts like objects, processes, structural and procedural relationships. The document also presents a case study of modeling an epaper project in OPM and compares OPM to UML, finding OPM better supported understanding of system dynamics. Tools like OPCAT for OPM modeling and collaboration are also summarized.