The frame of communication which is present between two medium is known as session in PHP, and the session is put into to use for storing the data into a cloud server instead of the user’s personal computer. A session a process to store information, which can be used by multiple other pages.

Let’s understand this when you work with the web application, from the starting till the end point. That point is known as the session. Your computer recognises it, but a web server doesn’t. In PHP we use session variables to get rid of this problem; session variables solve this problem by saving the user information.

Sessions are better than cookies

Even though cookies, not the cookies we like to eat, are used to store data related to the user, there are severe and vulnerable security issues related to them. Since they are stored in the user’s computer, they are easily hackable by the attackers. They can even modify the content and insert harmful digital elements which can cause severe system damage and massive breach in privacy.

It also leads to the breakdown of several applications. Apart from this cookies can also affect the overall performance of the browser and the system as well because it continues to add up space on the cache data.

We have mentioned some different steps involved in session in php:

Starting a PHP Session: session variables are created once the session in has been commenced. The session_start() function in PHP is used to initialise a new session, it also creates a fresh session id for the newly created user.

Create a new session in PHP 8

<?php 
  session_start();
?> 

Storing Session Data: $_SESSION[] superglobal array is used to work with session in PHP. The availability stored data can now be accessed any time during the lifetime of a session.

Following PHP code is used to save a session with two variables named as name and age:

<?php
  session_start();
  $_SESSION["name"] = "John";
  $_SESSION["age"] = "30";
?>

Accessing Session Data: the data just created is called session_start() and once the corresponding key has been passed to the $_SESSION associative array.

The session in php of the access of a normal session data with two different kinds of PHP session variables namely Age and Name is shown in the segment below:

<?php 
    session_start(); 
    echo 'The Name of the employee is :' . $_SESSION["name"] ;  
    echo 'The Age of the employee is :' . $_SESSION["age"] 
?>
/* 
  The Name of the employee is: John
  The Age of the employee is: 30
*/

Destroying Certain Session Data: To remove specifIc session data in PHP, The unset method is mixed with corresponding php session variable along with $_SESSION associative array.

In the below example we are setting up “age” session variable with associative php session array.

<?php 
   session_start(); 
   if(isset($_SESSION["name"])){ 
      unset($_SESSION["age"]); 
   }
?>

Destroying Complete Session: The session_destroy() method is used to completely remove a session in PHP. The session_destroy() method is absolutely free from the requirement of a parameter.

<?php
   session_start(); 
   session_destroy(); 
?>

Important Points

• PHP engines generate random session IDs for the session in PHP
• The session data is efficiently stored on the cloud server. Therefore, there is no requirement to have the array sent with every browser request.
• The session_start() method is being called at the starting point or before any result is produced.