This document provides an overview of database management systems and their basic concepts. It defines a database as a collection of related information stored and organized so that it can be accessed by multiple users. An effective DBMS eliminates redundant data, integrates existing data files, and allows data to be shared and changes to be easily incorporated. The objectives of a DBMS include consolidating files, providing program and file independence, offering versatile access, ensuring data security, and facilitating program development and maintenance. Key concepts discussed include the entity-relationship model, normalization, and the four main functions of a DBMS: data definition language, data manipulation language, transaction processing, and data access language.