The assignment content describes the design and specification of a new billing system that handles customer billing, accounts receivable, and order and shipping. The system takes in customer information including name, address, phone number, email, password, product orders, dates, and quantities. The system processes this input data to generate different scenarios for the flow of information and outputs, including delivery status, overdue amounts with taxes, and blocked shipping. The assignment also includes an Entity Relationship Diagram (ERD) that represents the flow of information from each level of classes.