Perl is a very popular web-oriented programming language, that is designed to set up CGI scripts along with a variety of apps. It is really useful as you don't need to write the same code repeatedly so as to have some process executed several times, but you will be able to employ modules. They are pre-defined subroutines or sets of tasks that can be called and executed inside a script. This means that, you will be able to include only a reference to a given module in your code rather than using the whole module code time and time again. In this way, your script will be shorter, thus it shall be executed a lot quicker, not mentioning that it'll be much easier to maintain and modify. When you want to employ some third-party ready-made Perl script as an alternative to creating your own, it will probably need particular modules to be pre-installed on the website hosting server.