n Information System is a coherent collection of data that can be stored, processed, and retrieved, to supply useful content to human beings. Most information these days is stored in databases, which are organized sets of data that can rapidly be input, calculated upon, and output. Information systems are used in business, to help process customer orders, organize inventory, calculate payroll, etc. Banks and securities firms are completely dependent on information systems to store customer account records and to process financial transactions. Information systems are an integral part of modern life.