A purely Web-based application is based on open Web standards, fully delivered over the Web for any Web browser or platform while being dynamic and interactive. Purely Web-based applications are easy to support (updates can be made as often as needed), fast to author, easy to distribute, and any user can run them without installing any software. This approach eliminates complex installation and deployment and provides some level of consistency with Web standards across platforms.

Applications are moving online whether they are Web-enabled versions of existing desktop applications (like Microsoft Smart Client applications) or whether they are built from the ground up to be purely Web-based.

To be purely Web-based, applications must be designed to have these characteristics:

• Zero Footprint – No plug-ins, downloads or ActiveX controls required. A pure Web-based application can operate as a standalone application in the Web browser.
  
• Dynamic User Experience– Goes beyond static content displayed in the browser to offer user interactivity like that of a desktop application with immediate responsiveness. For example, in an Employee portal, an employee may re-order or move content modules around to see Employee birthdays first, or a user could edit, update, and delete customer accounts in a CRM application right in their Web browser.
  
• Open, Interoperable with Cross-Platform Support - If purely Web-based, Web applications should work across all standard browsers and platforms and not be limited to being downloaded, installed, and configured for certain platforms.
  
  It doesn't make sense to just develop applications for Internet Explorer with other browsers like Firefox, Safari and Opera gaining popularity and market share. And, the Web is itself an open platform. Web technologies like AJAX, for example, are available to allow effective development of applications that run on all the major browsers and operating systems.
  
• Immediate Access from Anywhere - Web-based applications also do not have to be downloaded, installed and configured. This is a powerful advantage to leverage from the Web.
  
  Users want to use applications from any computer from any location, for example, most people now expect to be able to log in anywhere to check bank account balances or email from work, home and while on the go. Users should be able to access their email or their bank accounts online to check balances, use online bill pay, and so on regardless of the computer they are using or that computer’s system configuration.
  
• Easy Deployment and Updates - Web-based applications are always current, always updated to the latest release. Users do not have to remember to upgrade or be interrupted or prompted to download and install updates.
  
• Dynamic and Interactive– Leveraging open technologies, for example like AJAX, pure Web-based applications go beyond static content displayed in the browser to offer user interactivity like that of a desktop application with immediate responsiveness.
  
  For example, in an Employee portal, an employee should be able to click and move or change the order of content modules to see Company news first and Employee Birthdays second, or a user could edit, update, and delete customer accounts in a CRM application immediately, right in their Web browser.