Okay, I answered my own question.
If you've used C/C++, then you'll pick this up easily. There are two variables, "$argc" and "$argv".
$argc is "argument counter". It's an integer that represents the number of arguments passed to the script PLUS ONE (the name of the script being executed).
Example, "# php crap.php crap rocks"
$argc would hold the value "3".
$argv is "argument value". It's an array that contains an argument (as a string) in each array key, with the name of the script being in $argv[0] and the arguments passed being held after that.
Example, "# php crap.php crap rocks"
$argv[0] = "crap.php"
$argv[1] = "crap"
$argv[2] = "rocks"
Make sense? I'm pretty sure that's how things go anyway, I haven't actually typed out any code for it yet, but I'm about to do so. So if I'm wrong, I'll come back and fix this post