The **`unset()` function in PHP** resets any variable. If unset() is called inside a user-defined function, it unsets the local variables. If a user wants to unset the global variable inside the function, then he/she has to use `$GLOBALS` array to do so. The `unset()` function has no return value.

The illustration below explains how a variable is `unset()`:​

# Examples
## Code 1
The coded example below unsets the local variable:

<?php 
$my_var='Hello User';
echo " before unset : ".$my_var;
echo"\n";
unset($my_var);
echo "after unset : " .$my_var;
?> 

## Code 2
The coded example below unsets the global variable using `$GLOBALS` array:

<?php 
$my_var='Hello User';

function unset_var()
{
  global $my_var;
  echo "Before unset and inside function : ".$my_var."\n";
  unset($GLOBALS['my_var']);
}
echo "Outside function before using function : ".$my_var."\n";
unset_var();
echo "Outside function after using function : ".$my_var."\n";
?>

> The error in the codes occurred because the code tried to print the *unset* variable.

The **`unset()` function in PHP** resets any variable. If unset() is called inside a user-defined function, it unsets the local variables. If a user wants to unset the global variable inside the function, then he/she has to use `＄GLOBALS` array to do so. The `unset()` function has no return value.

The illustration below explains how a variable is `unset()`:​

## Code 2
The coded example below unsets the global variable using `＄GLOBALS` array:

What is the PHP unset() function?

The unset() function in PHP resets any variable. If unset() is called inside a user-defined function, it unsets the local variables. If a user wants to unset the global variable inside the function, then he/she has to use $GLOBALS array to do so. The unset() function has no return value. The illustration below explains how a variable is unset():​ 