This report presents a comprehensive system analysis and design for the QuickCabs online booking system, employing various UML diagrams to illustrate the system's functionality. The report begins with an introduction outlining the project's objectives, followed by detailed use case descriptions that define the interactions between actors (customers, system administrators, and managers) and the system. Each use case, such as updating personal details, checking taxi availability, modifying taxi information, and updating driver details, is thoroughly described with scenarios, triggers, preconditions, postconditions, and flow of activities. The report then proceeds with visual representations, including a use case diagram, activity diagrams, sequence diagrams, a domain model class diagram, a state machine diagram, and user interface designs for registration, login, checking availability, and booking confirmation. These diagrams provide a clear understanding of the system's architecture and user interactions. The conclusion summarizes the benefits of the new booking system for the company and its customers, emphasizing the ease of use and improved customer experience. The report concludes with a bibliography of cited sources.