This report provides a comprehensive overview of computer systems, starting with their roles in various environments such as education, banking, gaming, and hospitals. It details the hardware components like motherboards, RAM, CPUs, and video cards, as well as software components including system and application software. The report also covers the design specifications for meeting client needs, evaluating system suitability, building and configuring computer systems, testing procedures, and routine maintenance tasks such as defragmentation, antivirus updates, and driver updates. Furthermore, it discusses hardware and software upgrades to keep the system up-to-date, providing a thorough understanding of computer system functions and maintenance.