Following are extracted from the plugin home page.
Delete cookie:
// Returns true when cookie was found, false when no cookie was found...
$.removeCookie('the_cookie');
// Same path as when the cookie was written...
$.removeCookie('the_cookie', { path: '/' });
Note: when deleting a cookie, you must pass the exact same path, domain and secure options that were used to set the cookie, unless you're relying on the default options that is.
Comments
You can use jquery.cookie plugin.
Following are extracted from the plugin home page.