Over the last few years, various interface technologies have been developed that expand on CGI. At the same time, they are trying to address one of its main shortcomings: reloading the script with each new user query.
ASP (Active Server Pages): ASP was developed by Microsoft for its own server, but is now available for different types of servers. The ASP interpreter is integrated in the web server, so that a new process does not need to be started for its use. ASP commands can be directly written into the HTML pages. Much like CGI, ASP can be used across multiple programming languages.
PHP: Besides Perl, PHP is among the most widely-used script languages in web development. Much of what a CGI script can do, PHP can do too. The PHP interpreter, however, is directly integrated with the web server.
ColdFusion: ColdFusion was originally developed for Windows, but is now available for various Unix platforms as well. The ColdFusion Interpreter is integrated into the web server, much like the other CGI alternatives. Using existing tags or individual control elements, HTML pages can be modified. In addition, ColdFusion provides developers with a series of standard functions.
FastCGI: When using FastCGI, dynamic queries from a web server can be directly processed via a Perl interface without the processor having to be restarted. FastCGI is CGI compatible and is supported by a range of web servers.