PHP

Browser ↔ PHP server

A request goes out, PHP runs on the server, and plain HTML comes back. Click Request page to watch the round-trip and see the rendered result. This is a simulation — real PHP executes on a server, here it's mimicked in JS.

<!-- profile.php -->
<?php
  $name  = $_GET['name'] ?? 'Guest';
  $hour  = (int)date('G');
  $greet = $hour < 12 ? 'Good morning' : ($hour < 18 ? 'Good afternoon' : 'Good evening');
  $skills = ['PHP', 'MySQL', 'Laravel'];
?>
<h3><?= $greet ?>, <?= htmlspecialchars($name) ?>!</h3>
<p>Server time: <?= date('H:i:s') ?></p>
<ul><?php foreach ($skills as $s): ?><li><?= $s ?></li><?php endforeach; ?></ul>

Echo, variables & string interpolation

PHP's bread and butter is generating text. Type below and the "engine" runs an echo with double-quoted interpolation — just like the real thing (simulated output).

<?php
  $user  = "Linus";
  $count = 7;
  echo "Welcome back, $user — you have $count new messages.";
?>

Arrays & a foreach loop

Associative arrays are everywhere in PHP. This loop walks a price list and totals it — the simulated engine prints the same rows real PHP would.

<?php
  $cart = ['Coffee' => 3.50, 'Bagel' => 2.20, 'Juice' => 2.80];
  $total = 0;
  foreach ($cart as $item => $price) {
    printf("%-8s €%.2f\n", $item, $price);
    $total += $price;
  }
  echo "Total:   €" . number_format($total, 2);
?>

PHP still runs a huge share of the web

Despite being decades old, PHP powers an enormous slice of websites — largely thanks to WordPress, Laravel and a vast hosting ecosystem.

*Widely cited industry survey figures, shown here for context.

$_POST: handling a form

Submitting a form sends data to PHP via $_POST. Fill it in — the simulated handler validates and echoes a response page, exactly like a classic PHP form.