Provide a high level description of the Application Requirements.
Depict Context Diagram to give an overall picture of the system with an emphasis on data moving in and out of the overall process.
Depict Data Flow Diagram (Level 1) to describe data flows both in and out of each process. A narrative description for each of the processes should be in the following format:
Input Describe information required by the process.
Processing Describe the process in terms of its key functions.
Output Describe information produced and output from this process.