READ: Types of Applications

Intro

An application is a computer program. Some typical examples of software applications are word processors, web browsers, and media players.

Sometimes similar programs get bundled together in application suites like Microsoft Office, OpenOffice.org, or iWork. These examples all offer productivity applications for word processing, spreadsheets, presentations, and more.

Open source software is "software applications whose source code is published and made available to the public, enabling anyone to copy, modify and redistribute the source code without paying royalties or fees."

There are 3 types of computer applications. They are: 1) standalone applications, 2) client/server applications, and 3) SAAS (software as a service) applications.

Standalone applications

A program that installs all needed files and folders onto a single computer, and the program can be run from that single computer. Standalone applications are the most common type of computer programs today. They don't need to access any other computer to perform their function, besides the one on which they are installed. Examples: Open Office, Photoshop, iTunes.

Client/Server applications

A program that is installed on multiple computers and runs over a network. Typically, these programs consist of a single server application and several client applications. For example, a server application has been installed on Computer 1 in the image below.

http://upload.wikimedia.org/wikipedia/commons/thumb/f/fb/Server-based-network.svg/1000px-Server-based-network.svg.png

You install a client application on Computers 2, 3, 4, 5, 6, and 7. The program on Computers 2-7 have to access the application on Computer 1 in order to work. The popular game World of Warcraft is exactly this: Installing WOW on your computer does no good unless the game can access the WOW servers.

The primary benefit to client/server applications is that multiple people can be working with the same data at the same time. In the WOW example, multiple players are playing in the same game at the same time.

Another example of this is Instant Messenger. Have you ever noticed that your IM doesn't work if you aren't connected to the internet? That's because the client (on your computer) can't function without access to the server.

SAAS (Software as a service)

A software application that you don't install on your computer. The application runs entirely in your internet browser. Examples: Gmail (an email application that you never had to install on your computer - you just login and it works), Blogger, etc.



The 3 benefits of SAAS are
1) You don't have to install anything.
2) Software updates occur automatically, and if errors are found in the program, the company can fix it on everyone's computer with only one update.
3) You can access SAAS apps from any computer with internet access.

Sources: library.thinkquest.org/06aug/02220/glossary/index.html