A complete IB Computer Science A1.3 bundle covering operating systems and control systems from A1.3.1 to A1.3.7. Includes seven syllabus-aligned slide decks on the role and functions of operating systems, scheduling, polling and interrupts, multitasking and resource management, control-system components, and real-world control-system applications. Includes clear explanations, diagrams, worked examples, classroom activities, exam-style questions, retrieval practice, markschemes, and first-assessment-2027 preparation.