A cookie is often used to identify a user. A cookie is a small file that the server embeds on the user’s computer. Each time the same computer requests a page with a browser, it will send the cookie too. With PHP, you can both create and retrieve cookie values.
Cookies are text files stored on the client computer and they are kept of use tracking purpose. PHP transparently supports HTTP cookies.
There are three steps involved in identifying returning users −
Server script sends a set of cookies to the browser. For example name, age, or identification number etc.
Browser stores this information on local machine for future use.
When next time browser sends any request to web server then it sends those cookies information to the server and server uses that information to identify the user.
Setting new cookie
/*name is your cookie’s name
value is cookie’s value
$int is time of cookie expires*/