Anchor

An anchor is an HTML element <a> used to create hyperlinks, allowing navigation to other pages, resources, or sections within the same page. When the href attribute references a fragment identifier, e.g. #id, the link jumps to a specific section of the current document.

Anchors are frequently generated programmatically when building HTML output, navigation menus, or documentation pages. Developers must be careful to escape user-supplied content used in anchor href attributes to prevent XSS vulnerabilities.

<?php

// Generating an anchor safely in PHP
$url   = 'https://www.php.net/';
$label = 'PHP Manual';

// htmlspecialchars prevents XSS
echo '<a href="' . htmlspecialchars($url, ENT_QUOTES, 'UTF-8') . '">'
    . htmlspecialchars($label, ENT_QUOTES, 'UTF-8')
    . '</a>';

// Fragment / in-page anchor
echo '<a href="#section-2">Go to section 2</a>';

?>

Documentation

See also HTML anchor element - MDN.

Related : HyperText Markup Language (HTML), Cross Site Scripting (XSS), Universal Resource Locator (URL), parse_url(), http_build_query(), HTML Escaping, Link, Pound #