Because PHP is lightweight, platform-agnostic, and interpreted on the server side, its system footprint is exceptionally flexible.

1. Hardware Requirements

PHP itself does not demand heavy hardware resources, making it cost-effective to host. The exact specifications depend heavily on traffic volume and application complexity (e.g., lightweight CMS vs. enterprise microservices):

• Processor (CPU): Compatible with x86, x64, and ARM architectures. Multi-core processors benefit high-concurrency production servers.
• Memory (RAM):
  • Minimum: 512 MB RAM (sufficient for local development environments or minimal static setups).
  • Recommended: 2 GB+ RAM for standard production servers to efficiently manage concurrent user sessions, caching, and database queries.
• Storage: Minimal footprint (~200 MB for core binaries and extensions), plus additional storage space dictated by your application files, user uploads, logs, and databases.

2. Software Requirements

A functioning PHP stack (frequently referred to as a LAMP/LNMP stack) requires four main software layers:

• Operating System: Cross-platform support for Linux (Ubuntu, CentOS, Debian), macOS, and Windows (via IIS or WSL).
• Web Server: Apache (with mod_php or PHP-FPM), Nginx (via PHP-FPM), or Microsoft IIS.
• PHP Interpreter: Modern versions like PHP 8.x (incorporating features like the JIT compiler, performance boosts, and strict typing).
• Database System (Optional): MySQL / MariaDB, PostgreSQL, or SQLite depending on data persistence needs.

PHP Scripting Fundamentals

PHP code executes entirely on the server, rendering pure HTML to the client browser.

Core Syntax and Structure

• PHP Delimiters: PHP blocks are wrapped in canonical tags. Everything outside these tags is ignored by the PHP parser and treated as standard HTML. PHP
• <?php // PHP code goes here ?>
• Statements & Case Sensitivity: Every statement must end with a semicolon (;). Variables ($variableName) are strictly case-sensitive, whereas built-in language keywords and functions (like echo, if, while) are case-insensitive.

Basic Scripting Example

PHP

<?php
// 1. Variables and Data Types
$appName = "Inventory Dashboard";
$activeUsers = 142;
$isOnline = true;

// 2. Conditional Statement
if ($isOnline) {
    $statusMessage = "System is live and running.";
} else {
    $statusMessage = "System is under maintenance.";
}

// 3. Simple Function
function formatWelcome($name, $count) {
    return "Welcome to " . $name . "! Active users: " . $count;
}
?>

<!DOCTYPE html>
<html>
<head>
    <title><?php echo $appName; ?></title>
</head>
<body>
    <h1><?php echo formatWelcome($appName, $activeUsers); ?></h1>
    <p>Status: <?php echo $statusMessage; ?></p>
</body>
</html>

Essential Scripting Building Blocks

• Superglobals: Built-in arrays that give you global access to environment data, form submissions, and parameters (e.g., $_GET, $_POST, $_SESSION, $_SERVER).
• Control Structures: Standard logic blocks including if/else, switch, while loops, for loops, and foreach loops specifically designed for iterating through arrays.
• Code Inclusion: Modularize code across multiple files using include, require, include_once, or require_once.

Are you setting up a local development environment (like Docker, XAMPP, or Laravel Valet) or configuring a production server for a PHP project?