Computer Integrated Manufacturing (CIM) was developed to address these limitations by integrating manufacturing activities through the strategic use of information technology. Modern manufacturing demands real-time communication, seamless data sharing, and coordinated control across functions such as product design, process planning, production, inspection, and management. CIM architecture facilitates this integration by connecting not only machines and computer systems but also business processes, human resources, and organizational workflows into a cohesive manufacturing environment. This textbook, Fundamentals of Computer Integrated Manufacturing, is designed to provide undergraduate engineering students of APJ Abdul Kalam Technological University (KTU) with a clear and systematic understanding of CIM concepts, architecture, and applications. It presents CIM as a practical manufacturing philosophy in which computer-based systems communicate effectively throughout the entire product life cycle. By enabling direct use of design data for process planning and manufacturing, CIM reduces manual data re-entry, minimizes inconsistencies, and significantly enhances productivity. The book also discusses traditional integration approaches, such as customized system interfaces and centralized databases, highlighting their limitations related to cost, scalability, and flexibility. To overcome these challenges, the role of Product Data Management (PDM) systems as a key element of CIM architecture is introduced. Structured in accordance with the KTU syllabus and enriched with practical insights and case studies, this text serves as a comprehensive learning resource for students preparing to meet the demands of modern integrated manufacturing environments.