Computer System Architecture (MCA-301) discusses the architecture of computer systems. It defines a digital computer as a machine that stores and processes data using discrete binary digits. The document then outlines the basic components of a computer system including the central processing unit, memory, and input/output devices. It distinguishes between computer organization, which is concerned with how the hardware components work together, and computer architecture, which involves the structures and interfaces that software uses. The main types of computer architecture discussed are the Von Neumann and Harvard architectures.