A database management system (DBMS) is a software application that facilitates the organized storage, retrieval, and manipulation of data. This chapter explores key DBMS features, database models and languages, architecture, and design. The chapter begins with an introduction to the concept, paradigm shift, purpose, types, database management system, applications, advantages, and disadvantages of database management systems. It defines the function of database management systems (DBMS) in data management, including data integrity, security, and concurrency. Furthermore, this chapter examines certain key DBMS aspects and features, which aid in understanding the concept and application of DBMS. Data definition, database construction, data modelling, data manipulation, data storage and retrieval, concurrency control, data integrity and security, data backup and recovery, data dictionary, database administrators and users, data independence, database structure, and database are keys features of DBMS. The chapter begins by introducing the concept, paradigm shift, purpose, types, and applications of database management systems (DBMS), along with their advantages and disadvantages. It defines the role of DBMS in data management, focusing on aspects such as data integrity, security, and concurrency. Additionally, the chapter explores key DBMS features, including data definition, database construction, data modelling, data manipulation, storage and retrieval, concurrency control, integrity and security, backup and recovery, data dictionaries. It also highlights the significance of data independence and database structure in DBMS. The chapter next goes into database models and languages, laying the groundwork for structuring, organizing, and manipulating data within a database. The chapter goes on to discuss database architecture (two-tier and three-tier) as well as database conceptual, logical, and physical design. The chapter also looks at how DBMS can be integrated with other technologies to help with advanced data analysis and decision-making, such as data warehousing, data mining, and big data analytics.