CGI Script Introduction

Probably the most confusing issue for beginners is understanding the difference between CGI scripts and HTML.

CGI vs. HTML

For normal HTML pages, you upload text files to your ISP (via FTP, which FrontPage can automate). When someone views your site, their browser displays the page by interpreting the HTML. The "work" is done by the viewer's browser -- the browser must read the HTML and figure out how to layout the page and display it for the viewer.

Scripts are a bit different. They are mini-programs that reside on your ISP. When the view clicks on a link to a script, the *server* (not the bowser) has to go off in the background, run the program, and return the results to the viewer's browser.

ISP Issues

The important concept here is that the scripts run as little programs on your ISP's computer. That's why it's important to know what operating system the ISP is using. It's sort of like if you have a program that runs on Windows, you can't run that same program on a Macintosh (in most cases). So, the person that wrote that program has to know that you want to run it on a Windows platform. The same is true for CGI scripts.

In addition, not all ISPs will let you run CGI scripts on your web account. And other ISPs will restrict which CGI scripts you can run. Those are important pieces of information to have when you are investigating ISPs.

Installing CGIs

To install a CGI script requires not only uploading the script to your website (like you do for HTML pages). You must also do some configuration to set up the script to run properly. To do this, you need to have some basic familiarity with the way web servers and CGI programs work.

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