Database Management System (DBMS)

A database management system (DBMS) is system software for creating and managing Database. The DBMS provides users and programmers with a systematic way to create, retrieve, update and manage data.

A DBMS makes it possible for end users to create, read, update and delete Data in a database. The DBMS essentially serves as an interface between the db and end users or ensuring that data is consistently organized and remains easily accessible.
The DBMS manages three important things: the data, the database Engine that allows data to be , developers won't have to modify programs just because changes have been made to the database.
With relational DBMS's RDBMS, this API is SQL a standard programming language for defining, protecting and accessing data in a RDBMS.

Popular types of DBMSes

Popular database models and their management systems include:
Relational database management system (RDMS)  - adaptable to most use cases, but RDBMS products can be quite expensive.
No SQL DB - well-suited for loosely defined data structures that may evolve over time.
In-memory database management system (IMDBMS) - provides faster response times and better performance.
Columnar database management system (CDBMS) - well-suited for data that have a large number of similar data items.
Cloud-based data management system - the cloud provider is responsible for providing and maintaining the DBMS.

Advantages of a DBMS

Using a DBMS to store and manage data comes with advantages, but also overhead. One of the biggest advantages of using a DBMS is that it lets end users and application programmers access and use the same data while managing data integrity. Data is better protected and maintained when it can be shared using a DBMS instead of creating new iterations of the same data stored in new files for every new application. The DBMS provides a central store of data that can be accessed by multiple users in a controlled manner.
Central storage and management of data within the DBMS provides:

• Data abstraction and independence
• Data security
• A locking mechanism for concurrent access
• An efficient handler to balance the needs of multiple applications using the same data
• The ability to swiftly recover from crashes and errors, including restartability and recoverability
• Robust data integrity capabilities
• Logging and auditing of activity
• Simple access using a standard application programming interface (API)
• Uniform administration procedures for data

Another advantage of a DBMS is that it can be used to impose a logical, structured organization on the data. A DBMS delivers economy of scale for processing large amounts of data because it is optimized for such operations.
A DBMS can also provide many views of a single database schema. A view defines what data the user sees and how that user sees the data. The DBMS provides a level of abstraction between the conceptual schema that defines the logical structure of the database and the physical schema that describes the files, indexes and other physical mechanisms used by the database. When a DBMS is used, systems can be modified much more easily when business requirements change. New categories of data can be added to the database without disrupting the existing system and applications can be insulated from how data is structured and stored.
Of course, a DBMS must perform additional work to provide these advantages, thereby bringing with it the overhead. A DBMS will use more memory and cpu than a simple file storage system. And, of course, different types of DBMSes will require different types and levels of system resources.