We can get the modulus of two number by using math function modulus (%). This is same as remainder of a math division process of two number. Let us see this by the example script.
fmod(): reminder (modulo) of division →
We can see the modulus of 160 and 15 is equal to 10. Same way the reminder or modulus is 0 if two numbers are 150 and 10.

$num1 = 160;
$num2 = 15;
echo "<P>The value of variables is $num1 & $num2</P>";
$result = $num1 % $num2;
echo "<P>The modulus of these numbers is $result</P>";

Output

The value of variables is 160 & 15
The modulus of these numbers is 10

Finding odd or even number

All even numbers will have modules or reminder as zero when divided by 2.
Here is the code

$number=97;
if($number%2==0){
echo " $number is a even number ";
}else{
echo " $number is an odd number ";
}

Sum of digits of a number

<?php
$t1=1234321; // Sample number
$sum=0;
while($t1>0){
$d=$t1%10; // reminder of division
$sum = $sum + $d;
$t1=floor($t1/10); // floor value
}
echo $sum;
?>

Reverse the number

<?php
$t1=1234; // Sample data
$t1_reverse=0;
while($t1>0){
$d=$t1%10; // reminder of division
$t1_reverse = $t1_reverse * 10 + $d;
$t1=floor($t1/10); // floor value
}
echo $t1_reverse;
?>

Output

4321

Making alternate rows in different colors

While writing output of a series of records from database table or from any other sources we can make alternate rows of different colors by using modulus function.

Here two style class are defined. Based on modulus value one of them is assigned to as class property of the row of the table.

Here is the code

<html>
<head>
<title>(Type a title for your page here)</title>
<style>
table.t1 tr.r1 td { background-color: #f1f1f1; }
table.t1 tr.r0 td { background-color: yellow; }
</style>
</head>
<body>
<?PHp
$i=1;
echo "<table class='t1'>";
for($i=1; $i<=10; $i++){
$m=$i%2;
echo "<tr class='r$m'><td>This is row No : $i</td></tr>";
}
echo "</table>";
?>
</body>
</html>