What is Cookie?

• What is a Cookie?
  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.


• How to Create a Cookie?
  

  Syntax:

  setcookie(name, value, expire, path, domain);
  

  Example -

  setcookie("user", "Alex Porter", time()+3600);


• How to Retrieve a Cookie Value?
  The PHP $_COOKIE variable is used to retrieve a cookie value.
  

  Example -

  // Print a cookie
  echo $_COOKIE["user"];
  // A way to view all cookies
  print_r($_COOKIE);


• How to Delete a Cookie?
  When deleting a cookie you should assure that the expiration date is in the past.
  // set the expiration date to one hour ago
  setcookie("user", "", time()-3600);