The primary function of a Database Management System (DBMS) is to store, retrieve, and manage data effectively. A DBMS provides an interface for users to create, read, update, and delete data in databases while ensuring data integrity and security. It supports various data models, such as relational or NoSQL, and allows for complex queries to extract valuable information efficiently. By managing data relationships and enforcing data consistency, a DBMS plays a crucial role in applications ranging from enterprise systems to small-scale software solutions.