<?php

$txt = "Hi Hello world!"; 
$x = 5; 
$y = 10.5;

?>
                               

Difference Between ‘ ’ and “ ” 

                              
<?php 
 $variable = "name"; 
 $novariable = 'My $variable will not print!';
print($novariable); 
 print "<br>"; 
 
 $novariable = "My $variable will print!"; 
 print($novariable); 
?>
                              

Scope of Variable  - Global - Without keyword 

                                
<?php
$a = 5;
function myFunction() { 
 echo "<p>Variable a inside function is: $a</p>"; 
}
myFunction();
echo "<p>Variable a outside function is: $a</p>";
?>

Scope of Variable  - Global - With keyword 

                                
<?php
$x = 5; 
$y = 10;
function myFunction() { 
global $x, $y; 
$y = $x + $y; 
}
myFunction(); 
echo $y; 

?>

Using Global keyword with Array

                                
<?php
$x = 5; 
$y = 10;
function myFunction() { 
$GLOBALS['y'] = $GLOBALS['x'] + $GLOBALS['y']; 
}
myFunction(); 
echo $y; 
?>