This report provides an overview of object-oriented system analysis and design (OOAD), focusing on its application to an online student registration system. It begins by defining OOAD and object-oriented system analysis (OSA), highlighting the use of visual modeling and stakeholder interaction. The report includes a package diagram illustrating the system's architecture, detailing elements such as transcript login, course schedules, and prerequisites. It then discusses factors crucial for selecting a design strategy, including interface elements, consistency, business requirements, internal experience, project skills, project management, time frame, and cost. The report also explores client-server architectures (CSA), including 1-tier, N-tier, 2-tier, and 3-tier models, along with their advantages. Furthermore, it outlines key principles for user interface (UI) design, such as visibility, consistency, and minimizing user effort, and details the steps in the UI design process, from briefing and analysis to wireframing, prototyping, UI development, and interface evaluation. The report concludes by emphasizing the importance of usability and understandability in interface design.