Numbers (integers and real)
<?php
    $a = 1234;
    $b = 0777;
    $c = 0xff;
    $d = 1.25;
    echo "$a $b $c $d<br />\n";
?>
Output
1234 511 255 1.25
Strings
<?php
    $name = 'Rasmus $last'; // Single-quoted
    $str  = "Hi $name\n";   // Double-quoted
    echo $str;
?>
Output
Hi Rasmus $last
Booleans
<?php
    $greeting = true;
    if($greeting) {
        echo "Hi Carl";
        $greeting = false;
    }
?>
Output
Hi Carl
Dynamic Typing
<?php
    echo 5 + "1.5" + "10e2";
?>
Output
1006.5