Codice PHP:
<?php include_once $_SERVER['DOCUMENT_ROOT'] .
'/includes/helpers.inc.php'; ?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Recent Jokes</title>
<link rel="canonical" href="/recentjokes/">
</head>
<body>
<p>Here are the most recent jokes in the database:</p>
<?php foreach ($jokes as $joke): ?>
<?php markdownout($joke['text']); ?>
<?php endforeach; ?>
</body>
</html>
Perché si aggiunge a questo codice la riga:
<link rel="canonical" href="/recentjokes/">
?
A che serve?