A cookie is a flat file that stores tiny bits of information. It is stored on the client’s machine and is passed to the client when they visit your site. Each cookie can store anything from usernames to number of visits to a site. This tutorial will teach you how to create, retrieve, display, and delete cookies using php
1. Create a Cookie using PHP

Cookies are created using the setcookie() function. Below is an example of the setcookie() function
setcookie($name, $value, $expired, $path, $domain, $secure)
There are values that you can pass into the setcookie() function. The values are: name of the cookie, value of the cookie, the date the cookie expires, path where the cookie is available on the server, domain where the cookie is available, and where it is coming from a secure page.
The three values that we are worried about are $name, $value, and $expired.
Below is the php code to create a php cookie named "username". We set the value of the cookie to "Tom", and set the expiration date at one hour from now.
<?php
setcookie("username", "Tom", time()+3600);
?>
The cookie is set through the browser once a client visits your site or page that you set the cookie on.

2. Retrieve & Display a Cookie using PHP

Now let’s retrieve & display the cookie we just set. We retrieve the cookie using the predefined $_COOKIE array. Then we display the cookie using the echo function. Here is the code that will get you the cookie.
<?php
echo $_COOKIE["username"];
?>
3. Delete a cookie using PHP
We can delete the cookie when we are finished with it. Cookies are deleted by simply setting the expiration date to a past date. The example below will delete the cookie named username.
<?php
//www.*.com
setcookie("username", "Tom", time()-(60*60*24*365));
?>
That’s it! You have just created a cookie on the client’s machine, retrieved & displayed the cookie and deleted the cookie once you were done with it.
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