%...The Secret Modulus Page...%

The modulus operator is the only arithmetic operator used in programming that
was not taught in first grade, at least not to me.
It returns the remainder of a division operation.
For example, 10 / 3 equals 9, with 1 left over.  Long division is cool,
so 10 % 3 equals 1.  The correct way to read that is "ten modulo three".
I saw it in a C++ book, so it must be true.

{
	int $mod = 10 % 3;
	print ($mod + "\n");
}

The modulus operator can do some very cool things.  For example:
Number wrapping, think screen wrapping in Asteroids.
Suppose you want to constrain an input number to a number between 0 and 10.
if the number reaches 10, go back to zero and start over.
This example uses a loop.

{
	int $i;
	int $mod;
	for ($i = 0; $i < 100; $i++)
	{
		$mod = $i % 10;
		print ($i + " Screen wrap : " + $mod + "\n");
	}
}

You can also use it to find out if a number is odd, or even by moduloing (not sure of the correct terminology there) by 2.
This example uses a loop and conditional statements.

{
	int $i;
	for ($i = 0; $i < 100; $i++)
	{
		print ($i + " is ");
		if ($i % 2 == 0 )
			print "even.\n";
		else
			print "odd.\n";
	}
}


Keep the modulus in mind, because one of the first scripting exercises uses it quite a bit.