Pengenalan variabel

<?php
$a = "Bayu";
$b = "15";
$c = "14.5";
$d = "false";
//menampilkan data
echo "$a";
echo "<br />";
echo "$b";
echo "<br />";
echo "$c";
echo "<br />";
echo "$d";
echo "<br />";

// variabel yang berisi perkalian
$detik_per_hari = 60 * 60 * 24;
echo "Dalam 1 hari terdapat $detik_per_hari detik";
echo "<br />";

$person = array("Joko","Ani","Maicel","Geby");
// mengaksess array
echo $person[0];
echo "<br />";
echo $person[1];
echo "<br />";
echo $person[2];
echo "<br />";
echo $person[3];
?>