This design document mainly consists of State Machine/ Activity Flow Diagrams, Class Design, Internal Data Structures, Architectural design, User Interface and Testing. The main purposes of this design document are listed below.
1. Precise understanding of the requirements and constraints related with the programming language, and User Interface.
2. System decomposition into manageable units or modules
3. Abstraction of the system implementation with the help of classes
4. Provide a basic outline of the User Interface of the online shopping mall.