Client Server Model

* What is the client server model ?

   - Client server model is the importaint model in application and web world today.This model consists of  a server and clients.Server is where provide bussiness logic,that handles requests from client and responds the particular information to client.Client is where interact with user that recieve information from user , after that send to server to able to receive a particular  response and display information for user.

   -Today there are a lot of application and web using the client server model such as if you want to copy a file from another computer,you would use a client to access the file on the server.In other words,the server serves data to the client.(Source: http://www.answers.com/Q/Example_of_client_server ).

* Why is it used ?
  
   -The client server model is used beacause it provide modern techniques such as object oriented model ,ect and this model has the hight security.

* When is it used ?

   -The client server model is used when you want to create a web application.That communicate user.

* Note: A application is the collection of program designed to perform a particular task.Different application are required for different purposes.Based on the layer on which application is run and the accessibility to be given to user ,the applications are classified as below:
   - Desktop application.
   - NetWork application.
   - Web application.

The advantages of web application over desktop application :
   - Easer access to inforamation.
   - Lower maintainane and deployment cost.
   - Platform independent.
   - Wider visibility.

The application has three components.The prensentation layer,the application layer ,also know as business layer and the data access layer.Based on this structure,following is the four application architecture:
   - One-tier architecture.
   - Two-tier architecture.
   - Three-tier architecture.
   - N-tier architecture.