Following is an ER diagram for a railway reservation system. It illustrates the various elements involved in the reservation system. The diagram gives an overview of how a train reservation system works and how the customer can book different services offered by the train operator.The various entities involved in the reservation system include the customer, the ticket, the train services, the class, the train operator, and the payment. All of these elements work together to achieve the overall functionality inside the railway reservation system. This diagram can prove helpful when understanding the structure of the reservation system.