<?php
$str = "Hello, World!";

echo "Original String: $str<br>";
echo "String Length: " . strlen($str) . "<br>";
echo "Word Count: " . str_word_count($str) . "<br>";
echo "Reversed String: " . strrev($str) . "<br>";
echo "Uppercase: " . strtoupper($str) . "<br>";
echo "Lowercase: " . strtolower($str) . "<br>";
echo "Replace 'World' with 'PHP': " . str_replace("World", "PHP", $str) . "<br>";
echo "Substring (First 5 chars): " . substr($str, 0, 5) . "<br>";
?>