how to concat in php using echo code example

Example 1: concatenate string php

<?php 

// First String 
$a = 'Hello'; 

// Second String 
$b = 'World!'; 

// Concatenation Of String 
$c = $a.$b; 

// print Concatenate String 
echo " $c \n"; 
?>

Example 2: php concatenate two variables

$string = "the color is ";
$string .= "red";

echo $string; // gives: the color is red