Understanding ColdFusion

ColdFusion is a Web application development system that is designed to extend the functionality of your Web server. The development system is made up of several key components:

ColdFusion functions as a Web page preprocessor on the Web server, allowing you to embed sophisticated commands into your Web page. ColdFusion pages are plain text files that look much like HTML files. The only real difference between HTML files and ColdFusion files is the file extension, ColdFusion files have an extension of CFM. Other than that, whatever you can do in an HTML page, you can do in a CFM page. That, and a whole lot more.

The CFML language is made up of over 50 tags that provide all sorts of functionality, from database integration, to SMTP and POP support, to COM support, and programming constructs like conditional processing and looping. In addition, there are hundreds of third party add-on tags available, and you can write your own custom tags too.

So, how does ColdFusion work its magic? Well, it goes something like this:

  1. A user requests a ColdFusion page (one with a CFM extension). The Web server recognizes the page as being a ColdFusion page, and hands it off to the ColdFusion server for processing.
  2. ColdFusion parses and processes the page, executing any embedded tags and generating dynamic content.
  3. ColdFusion returns the page results (not the page itself) to the Web server, which in turn transmits it back to the user as HTML.

It is important to remember that ColdFusion only processes its own tags, and leaves any other code intact. Therefore, ColdFusion supports any and all client technologies, including Java, ActiveX, JavaScript, DHTML, VRML, HDML, and whatever else you'd care to throw at it.