<?php	
// this is compulsory statement if you want to access session variable in the page. This indicates that we are going to access session variables in this page
session_start(); 
// store session data
$_SESSION[‘userid’]=1;
//retrieve session data
echo "Userid=". $_SESSION[userid];
session_destroy();  // will reset your session and you will lose all your stored session data.
?>
This very basic use of session say now you want to change the value of session and want to check if the session exits.
<?php
session_start();
if(isset($_SESSION['views']))
	$_SESSION['views']=$_SESSION['views']+1;
else
	$_SESSION['views']=1;
echo "Views=". $_SESSION['views'];
?>

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