types of applications

Different Types of Applications

1. Command Line Interface:

· A Command Line Interface (CLI) is old fashioned user interface to an application or OS where the user will type a command on the visual command prompt then press enter and the system will responds according to that command instead of selecting an icon or menu item.

· In CLI the inputs are given only in the form of text and the output is also in the form of text only that is the entire visual command prompt only displayed in the form of characters but not images.

· In CLI we do not use any mouse or graphical controls or the CLI do not support for the graphics, pictures etc…

· The CLI is now embedded in many of the operating systems like Microsoft Windows, Mac OS and Linux OS etc…

· USAGE: A user wants to create an account for a mail system he uses the following syntax to create the account by using following CLI command

CREATEACCOUNT account Name [account Type] [external] [settings]

· The most familiar example of a CLI to many people is MS-DOS, Linux etc..

2. Graphical User Interface:

· A Graphical User Interface is a human-computer interaction where the user can manipulate the operating system using icons, menus, windows etc… and which can be manipulated by mouse also.

· A major advantage of GUI is that any people who do not have any knowledge about the OS also is in a position to manipulate and is easy to use for him i.e., it is easy to use and speed up the process of usage.

· GUI also takes full advantage of the most powerful ‘multitasking’ ability so that we can have many programs running simultaneously in an Operating System.

· The flexibility of GUI is made possible by various parts such as frames, scrollbars, tabs, buttons which will constitute a regular window.

· The best examples of GUI are the operating systems like Windows, Apple Mac OS which are the most user-friendly.

COTS :( Stand-alone System)

· COTS products include software and hardware products that are ready-made and available for sale to the general public.

· COTS products are typically installed in existing systems and do not require customization.

· A Stand-alone system is a system which is independent of the other systems and is not connected externally to any system in the network.

Thin Clients:

· A Thin Client is a computer or a computer program which depends heavily on other computers for its actual computational roles.

· A thin client application is simply one which relies on its server to process most or all of its business logic.

· Since all the thin clients are connected to a single server and if the server fails entire clients will be collapsed leading to the single point of failure.

· The server should be the most robust in hardware to handle several clients while the thin clients are made of cheaper hardware.

· Ex: OpenThinClient which includes the java-based management software and java-based server component is the best example for thin clients.

Thick Clients:

· A Fat client or Thick Client is a client computer in client-server architecture which provides rich functionality independent of the central server system.

· A Thick Client has the ability to perform many functions without connection to the network.

· A thick client server does not require as high a level of performance as a thin client server.

· Thick Clients produce better multimedia performance and are more flexible than thin clients.

· Thick Clients also have higher server capacity where the server need not do much of the work because most of the work is carried by the clients.

· Ex: IBM Lotus Notes is an example for the Thick Clients where in different applications such as e-mail, Calendars etc... Are embedded in it.

3. Client-Server Applications:

· Client-server system is a system where the services are offered in the request-response manner.

· In Client-Server model one system at the client side will request for the service to the server and in response to it the server will provide the requested result for that service.

· Client–server architecture enables the roles and responsibilities of a computing system to be distributed among several independent computers.

· All the data is stored in the server which has high security controls than many clients and hence this system or the applications that are built on this model are more secured than other systems.

· The important protocols that are used in the Client-Server applications are

TCP/IP Protocol (Transmission Control Protocol/Internet Protocol)

FTP (File Transfer Protocol)

TELNET

DNS (Domain Name Server)

Ex: Internet is the best example for the client-server applications where the client sends the request and the server sends back the response to the client.

4. Legacy Applications:

· A legacy system is an old method, technology or application program that are currently being used because it still meeting the users' needs.

· Legacy applications are those that are inherited from languages, platforms, and techniques that are used earlier.

· A legacy system may include procedures or terminology which is no longer relevant in the current context.

· There are many reasons to use these legacy systems because

--those systems many be working well for many years from now

--the costing to replacing the system may be high

--the usage of the latest system may not be known to the users

· Ex: Mainframes is an example for the legacy systems where the system uses COBOL language.

5. Intranet Applications:

· Intranet is the private network system where it uses internet protocols to protect the data in particular organization.

· Intranet in an organization is used to access the data from the local server fast and easier way so that the employer may use it according to their convenience.

· Intranet is also used to deploy the applications and also to develop the applications within the organization to support business operations.

· Intranet also allows the organizations to promote common corporate culture, enhance collaboration, and updates are sent immediately.

· Ex: IDG Management System developed an intranet application called IDGMS to maintain the data of the applicants applying for the post of nurses in USA, Australia etc…

6. Internet Applications:

· Internet applications are the web based applications where they have similar properties of the regular applications and these are accessed through the browser.

· The advantages of the internet applications are

--Web browsers are used to search the required content

--Sharing and file transfer can be done using network protocols like TCP/IP

--Applications are also available to mail and chat and messaging

--e-learning is made easier with the internet applications

· Online gaming, online shopping, online sales, online booking, online trade and travel are made easier with the advent of internet applications.

· Rich internet applications are more attractive to use them and this improved the user satisfaction and also productivity of those applications.

· Ex: All the applications that are deployed on the web like G-mail, orkut, yahoo mail, cricinfo etc… are the examples of internet applications.

7. Software Development Kit :( API based applications)

· A Software Development Kit is a kit that consists of set of different development tools which allows the creation of a software package.

· It is also called an API where it has some files that are used as an interface to a particular programming language.

· In simple SDK is a programming package that enables a programmer to develop applications for a specific platform.

· Typically an SDK contains one or more API’s, Programming tools and documentation.

· Ex: Each and every company that produces their own product will have their own SDK for that product. Some of them are iphone sdk, eclipse sdk etc….

8. Web Services:

· Web services are the API’s that are accessed via HTTP protocol and are executed on remote systems hosting the requested services.

· It also defined as the software system designed to support interoperable machine-to-machine interaction over a network.

· Web services are broadly divided into two categories

a) Big Web services: These use XML messages that follow the Simple Object Access Protocol (SOAP) standard and have been popular with traditional enterprise.

b) Restful Web services: it is a prerequisite for automated client-side code generation in many Java and .NET SOAP frameworks.

· Web APIs allow the combination of multiple web services into new applications known as mashups.

· Ex: Knowledge based web service is an example of web service where we can access and retrieve the data from a specified web page.