This document discusses object-oriented modeling and design. It provides an overview of key concepts in object-oriented thinking like objects, classes, polymorphism, and inheritance. It also describes object-oriented methodology, including analysis, system design, object design, and implementation. Additionally, it discusses object modeling technique (OMT) and the unified modeling language (UML), including the four main views (use case view, design view, process view, and implementation view) used in UML architecture.