PHP

html_entity_decode (PHP 4 >= 4.3.0, PHP 5, PHP 7, PHP 8) html_entity_decode — Convert HTML entities to their corresponding characters

<?php
$orig = "I'll "walk" the <b>dog</b> now";

$a = htmlentities($orig);

$b = html_entity_decode($a);

echo $a; // I'll &quot;walk&quot; the &lt;b&gt;dog&lt;/b&gt; now

echo $b; // I'll "walk" the <b>dog</b> now
?>