Scripts are files that activate dynamic actions on Web sites. There are many types of scripts. These are just a few that are fairly comon on Web sites.
.cgi
CGI stands for Common Gateway Interface. A .cgi file is a file that will run on the Web server and interact with the Web user. CGI files can be written with many different programming languages, like Perl, C, Tcl, and others. A CGI file does not have to have the .cgi extension, you might also see them in /cgi-bin directories on Web sites.
.pl
This indicates a Perl file. Many Web servers will run a .pl file as a CGI.
.js
A .js file is a JavaScript file. You can load your JavaScript files into the Web page itself, or you can write it in an external file and load it from there. If you write your JavaScript into the Web page you won't see the .js extension, as it will be part of the .html file.
.java or .class
While you probably won't come across a .java or .class file on a Web page, these files are often used to generate Java applets for Web pages.
There are many other types of script and program files as well that you might see on Web pages.
