This report provides a comprehensive overview of computer architecture, detailing its fundamental components, including memory, processors, and input/output devices, as well as the communication channels that connect them. It explores the three main elements of computer architecture: system design, instruction set architecture, and microarchitecture. The report traces the evolution of computer architecture across five generations, highlighting key advancements in each, from vacuum tubes and magnetic drums to integrated circuits and parallel processing. It also discusses the architecture of modern computers, including layers such as application, system software, and hardware. The report concludes by mentioning various computer architectures such as Von Neumann, Harvard, RISC, and CISC, providing a solid foundation for understanding computer systems.