The two are very similar. The practical definition of CGI (Common Gateway Interface) is any script or executable that is initiated by an HTTP request, executes on a Web server and returns an HTML response to the end-user. ASP (Active Server Pages) is a technology that produces very similar results to a CGI. ASP embeds a script within an HTML page. ASP pages embed special HTML code that is processed at the server before being returned to the user's browser. ASP can embed any type of script in it. In the Microsoft world, VBScript is the default scripting language most commonly used.
This was first published in May 2001