How to Start and Clear a Session in PHP

We here the term all the time called "cookie". In reference to the web a "cookie" is when a website stores information on a person's computer to be used at a later time. That later time could be 10 minutes or 30 days. A session is the same thing in essence except it is only valid while the user is on a website. PHP offers a very easy way to create and clear session information. Here is how it is done.

Difficulty: Easy

Instructions

1. To start a new session in PHP we use the code:
   session_start();
   
   This creates a brand new session and a unique session identification number which can be obtained by using the built in function code:
   session_id();

2. Once you have your session created you start adding values to your session by assigning the values what are called session variables. For example you can use:
   $_SESSION['firstname']='mike';
   
   Firstname is the session variable and 'mike' is its value. If you ever want to retrieve the value of firstname you would write this code:
   echo $_SESSION['firstname'];

3. Now that you know how to start a session and assign variables within a session, you need to know how to clear a session. This is simple. You use the built in function session_destroy();
   This will clear all of the variables and their values within a session, but it does not however clear the session_id value. That will remain.