What is DBMS- Database Management System

A database-management system (DBMS) is a collection of interrelated data and a set of programs to access those data. The collection of data, usually referred to as the database, contains information relevant to an enterprise. The primary goal of a DBMS is to provide a way to store and retrieve database information that is both convenient and efficient.

Database systems are designed to manage large bodies of information. Management of data involves both defining structures for the storage of information and providing mechanisms for the manipulation of information. In addition, the database system must ensure the safety of the information stored, despite system crashes or attempts at unauthorized access. If data are to be shared among several users, the system must avoid possible anomalous results. Because information is so important in most organizations, computer scientists have developed a large body of concepts and techniques for managing data.

Databases are widely used. Here are some representative applications:

• Banking: For customer information, accounts, and loans, and banking transactions.
• Airlines: For reservations and schedule information. Airlines were among the first to use databases in a geographically distributed manner—terminals situated around the world accessed the central database system through phone lines and other data networks.
• Universities: For student information, course registrations, and grades.
• Credit card transactions: For purchases on credit cards and generation of monthly statements.
• Telecommunication: For keeping records of calls made, generating monthly bills, maintaining balances on prepaid calling cards, and storing information about the communication networks.
• Finance: For storing information about holdings, sales, and purchases of financial instruments such as stocks and bonds.
• Sales: For the customer, product, and purchase information.
• Manufacturing: For the management of the supply chain and for tracking the production of items in factories, inventories of items in warehouses/stores, and orders for items.
• Human resources: For information about employees, salaries, payroll taxes and benefits, and for the generation of paychecks.

As the list illustrates, databases form an essential part of almost all enterprises today. Over the course of the last four decades of the twentieth century, the use of databases grew in all enterprises. In the early days, very few people interacted directly with database systems, although without realizing it they interacted with databases indirectly through printed reports such as credit card statements, or through agents such as bank tellers and airline reservation agents. Then automated teller machines came along and let users interact directly with databases. Phone interfaces to computers (interactive voice response systems) also allowed users to deal directly with databases—a caller could dial a number, and press phone keys to enter information or to select alternative options, to find flight arrival/departure times, for example, or to register for courses in a university.