This lecture covers the fundamental concepts of computer architecture, focusing on the von Neumann architecture and its layers of abstraction. It begins with an overview of the von Neumann architecture, explaining how programs and data are stored in the same memory. The lecture details the components of a Central Processing Unit (CPU), including the control unit, arithmetic/logic unit, and memory unit. It introduces the instruction set architecture (ISA), which defines what is visible to software and how it changes with each clock cycle. The fetch-decode-execute cycle is explained, illustrating how instructions are processed within the CPU. The lecture also addresses the question of whether registers are considered memory and discusses the importance of memory management units (MMUs) in protecting and managing memory. The instructor emphasizes the significance of CPU privileges and virtual memory, providing a comprehensive understanding of how these elements enhance the von Neumann architecture.