What does it mean when my CGIs fail with "Premature end of script headers" or "Internal Server Error"?

This means your script is not working correctly and it did not complete the action it was supposed to. Why does this happen? Well the most common reason is that the script does not have the proper permissions. What's probably happening is that when run on the command line, that script has the same permissions do, but when you run in the server, its permissions are equal to the permissions that...