Normally, what happens is that when we give a request to a web browser, the browser sends the request to the web server which tries to fulfill the requests by returning the requested data to the browser. But a web server’s capability is limited since there is much functionality that a web server does not allow us to do; for example, interacting with the database, validating user inputs, etc. A web server, basically what it does is locates the information and returns it to the browser. So for extending the functionality of a web server, web application server is used. It is a software program that is capable of doing all the functionalities that a web server cannot perform. Now what happens is that when a browser sends a request, the web server looks at the file extension of the requested URL. If the user requested a simple page like a HTML page, then the web server itself processes the request, but if the user requests a page that a web application server must process like a CFML page or CFC, then the web server passes on the request to the application server. The web application server processes the request and sends the result to the web server which sends on the result to the browser and the user is able to view the page.