DATABASE CONCEPTS - H2KINFOSYS

The database concepts is a major part of study for the testers, because data storage and processing is one the important requirement from the client. The information has to be stored in every organisation. e.g.: Banks, library, flight companies, hospitals, universities etc. The information is stored for the future reference. The information can be used for future reference to generate the reports. The data in any organisation has below roles:

data can be used to identify the problems, performance of various entities in organization.
data is used to analyse the various scenarios in the organisation.
data is used by the management for administration
data is used to provide the explanation for various events
data is used to monitor the performance and progress in organisations.
data is used for planning, monitoring and controlling.
data is used for making major decisions in the organisation.
Since the data plays very important role in any of the organisation, below factors become important:

Entity:
It is anything about which information can be stored. Eg: students, employees, courses, patients, departments, sales, raw materials, inventory, etc.

Data:
Data is an information about a particular entity.

Database:
Database is collection of information stored in organised way so that data can be accessed, managed and updated.

Database management system:
Database management system is software system to create, access, manage and update the database.

Questions:
What is database and DBMS?
Name a few DBMS?