Databases and database systems have
What is Dadabase system?
become an essential part of our everyday life.  We encounter several activities that involve some interaction with a database almost daily.  File based systems were an early attempt to computerize the manual filing system.  

This system has certain limitations.  In order to overcome the limitations of file-based systems, a new approach, a database approach, emerged.  A database is a collection of logically related data.  

This has a large number of advantages over the file-based approach.  These systems are very complex, sophisticated software applications that provide reliable management of large amounts of data.  

There are two different ways to look at the architecture of a DBMS: the logical DBMS architecture and the physical DBMS architecture. The logical architecture deals with the way data is stored and presented to users, while the physical architecture is concerned with the software components that make up a DBMS.
Databases and database systems

Ragement System cepts the physical architecture describes the software components used to enter and process data, and how these software components are related and interconnected.  
At its machi basic level the physical DBMS architecture can be broken down into two parts: the back end and the front end.  

The logical architecture describes how data in the database is perceived by users.  
It is not concerned with how the data is handled and processed by the DBMS, but only with how it looks.  
The method of data storage on the underlying file system is not revealed, and the users can manipulate the data without worrying about where it is located or how it is actually stored.  
This results in the database having different levels of abstraction such as the internal or physical level, the conceptual level, and the external or view level.  
The objective of the three level architecture is to separate each |  user's view of the database from the way the database is physically represented.  
Finally, we have a brief introduction to the concepts of database models.