Many scripts are freely available throughout the web and through other resources.
However, there are several parameters which need to be set to enable the scripts to run. Most of these scripts come with extensive documentation. The documentation describes the configuration certain lines in the script itself to enable it to work on your particular host machine, and often needs to know the location of certain programs on the server. This appears on the very first line of your perl script. Once your script is uploaded, it must be set so you can run it.