how to concatenate in php echo code example

Example 1: php append string

<?php
$a = "Hello ";
$b = $a . "World!"; // now $b contains "Hello World!"

$a = "Hello ";
$a .= "World!";     // now $a contains "Hello World!"
?>

Example 2: concatenate string php

<?php 

// First String 
$a = 'Hello'; 

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

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

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