System architecture refers to the structure of a software system or computer system, including its components, modules, interfaces, and data flows. It involves designing and organizing the system's hardware and software components to meet specific requirements and objectives. System architecture plays a crucial role in ensuring that a system is scalable, reliable, secure, and efficient. It involves making decisions about the system's overall design, including the choice of hardware and software components, the communication protocols used, and the organization of data and processes. Key concepts in system architecture include modularity, scalability, flexibility, and performance. A well-designed system architecture can help ensure that a system meets the needs of its users, is easy to maintain and upgrade, and can adapt to changing requirements and technologies. Overall, system architecture is a critical aspect of software and computer engineering, as it provides the foundation for building complex and reliable systems that can meet the demands of modern computing.