Database management software are sophisticated applications that manage small number of data to enterprise level data. The structure of a DBMS may be analyzed in 2 separate architectures
- Logical DBMS Architecture
- Physical DBMS Architecture
In this type of architecture, the user is concerned primarily with the look and feel of the data he or she will manipulate. There are no concerns related to how the data is stored or how it should be handled. That aspect is hidden from the user and the DBMS shields it. For example, in SAP ERP System, you can bring up a customer profile and you may be able to update the information or simply add more data. From that point, you will not be concerned on how and where the data will be stored. You simply click on the save button.
Physical DBMS Architecture
This aspect is concerned with the architecture related to manipulating the data being collected from the user and processing it. The physical architecture can be divided as follows: front-end and back-end divisions.
The front-end module is a simple interface that sits on top of the database and is used primarily for the interaction between the user and the database. The back-end part is concerned with the physical part of the database.
DBMS Software
When discussing DBMS software, I have decided to go over 3 specific ones. Microsoft SQL, Microsoft Access and MySQL. Even though Access is not really being used on large scale platform, it would be interesting to learn more about it since it's a very popular database management system which many students tend to deal with in early university years.
Access is available through Microsoft's productivity suite Office. It's a very powerful application that doesn't cost a lot of money. It allows you to create and manage a database with ease and through it's user friendly graphical interface, you may design tables, generate reports, or simply maintain the data. 
MySQL is available for free through the Open Source Agreement. It is being use primarily in conjunction to websites such as ecommerce or newsfeeds.
Widely used by many small or medium sized businesses, SQL server makes the task of managing a database more efficient. Businesses rely on it to manage enterprise level databases.
References:
http://www.cns-service.com/microsoft/images/sql-diagram.gif
http://www.dbmaker.com.tw/reference/manuals/tutorial/tutorial_03.html
