define header in php

PHP
<html>
<?php
/* This will give an error. Note the output
 * above, which is before the header() call */
header('Location: http://www.example.com/');
exit;
?>

/*
This will just redirect you to example.com
*/

<?php
$url = "https://example.com";
header("Location: $url");  
exit;
?>

/* I hope it will help you. Namaste */
Source

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