PHP Tutorial for Beginners & Beyond – 2025 Edition

Introduction to PHP

What is PHP?

PHP stands for Hypertext Preprocessor – a server-side scripting language used to build dynamic websites and web apps. You embed PHP in HTML to:

• Handle forms
• Connect to databases
• Process logic
• Generate dynamic content

History of PHP

PHP was developed in 1994 by Rasmus Lerdorf.
It started as simple scripts and evolved into a full-fledged programming language that powers:

• Facebook
• 📰 Wikipedia
• 🖋️ WordPress

Why Learn PHP in 2025?

PHP powers 70%+ of websites
Friendly for beginners
Massive community support
Essential for CMS platforms like WordPress and Drupal

Setting Up the PHP Environment

Install PHP on Windows / Mac / Linux

Download PHP directly from php.net
Or use a bundle (recommended) 👇

Use XAMPP / MAMP

• XAMPP – Best for Windows/Linux
• MAMP – Tailored for Mac

These include:

• Apache
• MySQL
• PHP

Your First PHP Script

Create a file named index.php:

<?php
echo "Hello, PHP World!";
?>

Save it in your server directory (htdocs for XAMPP)
Open in browser – Voilà, it works!

PHP Basics

Syntax

<?php 
// Your PHP code goes here 
?>

• Statements end with ;
• Use comments like:

// Single line
/* Multi-line */

Variables & Data Types

$name = "John";     // String
$age = 25;          // Integer
$price = 19.99;     // Float

Constants

define("SITE_NAME", "MySite");

Control Structures

Conditional Statements

if ($age >= 18) {
  echo "Adult";
} elseif ($age == 17) {
  echo "Almost there!";
} else {
  echo "Minor";
}

Loops

for ($i = 0; $i < 5; $i++) {
  echo $i;
}

Functions in PHP

Define & Call a Function

function greet($name) {
  return "Hello, $name!";
}

Variable Scope

• Local
• Global
• Static

Each determines visibility and memory behavior.

PHP Arrays

Indexed Array

$fruits = ["Apple", "Mango", "Orange"];

Associative Array

$user = ["name" => "Jane", "age" => 28];

Multidimensional Array

$matrix = [
  [1, 2],
  [3, 4]
];

Useful Array Functions

• array_push(), array_pop()
• in_array(), count()

Handling Forms with PHP

GET & POST

$name = $_POST['name'];

Validation & Sanitization

$name = htmlspecialchars($_POST['name']);

Or use:

$name = filter_input(INPUT_POST, 'name', FILTER_SANITIZE_STRING);

PHP and Strings

String Functions

• strlen(), strpos(), substr()

Concatenation

echo "Hi, " . $name;

File Handling in PHP

Read a File

$file = fopen("file.txt", "r");
$content = fread($file, filesize("file.txt"));
fclose($file);

Upload a File

$_FILES['file']['name'];

Always validate:

• File type
• File size
• File name

PHP with MySQL

Database Connection

$conn = new mysqli("localhost", "root", "", "myDB");

CRUD Operations

$sql = "INSERT INTO users (name) VALUES ('John')";
$conn->query($sql);

Sessions and Cookies

Session Example

session_start();
$_SESSION['user'] = 'John';

Set a Cookie

setcookie("user", "John", time() + 86400 * 30, "/");

Error Handling

Error Types

• Parse Errors
• Fatal Errors
• Warnings
• Notices

Try-Catch Block

try {
  throw new Exception("Oops!");
} catch (Exception $e) {
  echo $e->getMessage();
}

PHP Security Best Practices

Avoid SQL Injection

Use Prepared Statements:

$stmt = $conn->prepare("SELECT * FROM users WHERE name = ?");
$stmt->bind_param("s", $name);

Secure File Uploads

• Limit size
• Check MIME types
• Rename files

Prevent XSS

echo htmlspecialchars($user_input);

Object-Oriented PHP (OOP)

Classes & Objects

class Car {
  public $color;
  function __construct($color) {
    $this->color = $color;
  }
}

OOP Features

• Encapsulation
• Inheritance
• Polymorphism

Traits & Interfaces

Traits = Code sharing
Interfaces = Contract for methods

PHP Frameworks & CMS

Top Frameworks

• Laravel – Modern, clean, scalable
• Symfony – Enterprise-grade
• CodeIgniter – Lightweight

Popular CMS

• WordPress – #1 blog/site platform
• Joomla – Flexible
• Drupal – Powerful & customizable

Conclusion: What’s Next?

PHP is in 2025!
Mastering it opens doors to:

• Full-stack development
• WordPress customization
• Backend engineering roles

Next Steps:

• Build a project
• Join PHP communities
• Explore Laravel
• Master MySQL

Learn by doing. Make mistakes. Debug. Grow!

FAQs

1. Is PHP good for beginners?
Yes! It’s beginner-friendly and integrates well with HTML.

2. Is PHP still used?
Absolutely – powers over 70% of server-side websites.

3. What PHP framework should I learn?
Start with Laravel.

4. Can I mix PHP with HTML?
Yes! PHP is often embedded inside HTML.

5. Should I learn MySQL too?
Definitely, especially for database-driven apps.