SM - PHP

What skills does a PHP developer need?

Modern PHP is far from the language's older reputation

PHP is a server-side scripting language built specifically for the web — every request runs your script, renders a response, and exits, which makes the request/response model and superglobals ($_GET, $_POST, $_SESSION) worth understanding early. Modern PHP (7.4+) added strong typing, arrow functions, and match expressions that make it look a lot less like the PHP of a decade ago.

Because PHP talks directly to the browser and the database on every request, security is not optional: input validation, XSS and CSRF prevention, SQL injection defenses, and password hashing come up constantly, not just in theory.

Beyond the language itself, real PHP work happens inside a framework — usually Laravel or Symfony — backed by Composer for dependencies, PHPUnit or Pest for tests, and PSR standards that keep codebases consistent across teams.

The PHP Roadmap

Work through these in order, then pick a framework once OOP and databases feel solid

STEP 1

Introduction to PHP

What PHP is, how it got here, and what modern versions actually offer.

What is PHP? Evolution and History PHP Versions and Features

STEP 2

Development Environment

Get PHP running locally, alongside a web server and a database.

Installing PHP Local Server WAMP XAMPP MAMP LAMP

STEP 3

Learn the Fundamentals

Core syntax and the building blocks every PHP script starts from.

Basic PHP Syntax Variables and Scope Data Types Casting Data Types Constants echo / print var_dump / print_r

STEP 4

Arrays

PHP's workhorse data structure, in three shapes.

Indexed Arrays Associative Arrays Multi-dimensional Arrays

STEP 5

Conditionals & Loops

Control flow, plus the newer operators that shortcut common null checks.

if / else switch / match Loops Null Coalescing Operator Null Safe Operator

STEP 6

Functions

From basic declarations to the arrow and variadic forms modern PHP encourages.

Function Declaration Parameters / Return Values Default / Optional Params Named Arguments Variadic Functions Recursion Anonymous Functions Arrow Functions Callback Functions

STEP 7

File Handling

Include other scripts, and read or write to files in a few common formats.

require / require_once include / include_once Reading Files Writing Files File Permissions JSON Processing CSV Processing XML Processing

STEP 8

HTTP / Request Handling

How a PHP script sees an incoming request, and keeps state across them.

HTTP Methods $_GET / $_POST / $_REQUEST $_SERVER Super Global Variables Form Processing File Uploads Cookies Sessions State Management

STEP 9

Basics of Security

The defenses every PHP app needs before it touches real user input.

Input Validation Sanitization Techniques XSS Prevention SQL Injection CSRF Protection Password Hashing Auth Mechanisms

STEP 10

Working with Databases

Connect to a database safely, and keep queries fast as data grows.

PDO MySQLi Database Connectivity Object-Relational Mapping (ORM) Database Transactions Connection Pooling Database Migrations Performance Optimization

STEP 11

Object-Oriented Programming

The paradigm nearly every PHP framework is built around.

Classes and Objects Constructor / Destructor Properties and Methods Access Specifiers Static Methods and Properties Inheritance Polymorphism Abstract Classes Interfaces Traits Namespaces Magic Methods Dependency Injection Type Declarations

STEP 12

Frameworks & Tools

The ecosystem around the language — where most day-to-day work actually happens.

STEP 13

Advanced PHP Topics

Squeeze more performance out of a script, and know what's happening under the hood.

Profiling Techniques Caching Strategies Memory Management Configuration Tuning Configuration Files Environment Variables Executing System Commands Process Control Xdebug Zend Debugger

STEP 14

Performance Optimization & Web Servers

How PHP actually gets served in production, and what makes it fast.

Opcode Caching System Interactions Apache Nginx PHP-FPM

GitHub Projects

Real, buildable projects to put on your own GitHub

Laravel CRUD App

Start a fresh Laravel project and build a full CRUD app — models, migrations, controllers, and Blade views — to see a batteries-included framework in action.

Laravel ORM Migrations

Symfony Demo Application

Study and extend an official Symfony demo app to see how routing, dependency injection, and Doctrine fit together in a production-shaped project.

Symfony Dependency Injection Doctrine

Plain PHP REST API

Build a small REST API in plain PHP with PDO and no framework — a good way to feel exactly what a framework is doing for you before adopting one.

PDO REST API OOP

Tested Composer Package

Publish a small utility library on Packagist, following PSR standards, with PHPUnit or Pest tests and PHPStan wired into CI.

Composer PHPUnit PSR Standards

Frequently Asked Questions

Common questions from people starting out with PHP

Is PHP still worth learning?

Yes — PHP powers a large share of the web, including most WordPress sites and many large platforms built on Laravel and Symfony. Modern PHP versions added strong typing, arrow functions, and enums, which is a big shift from the language's older reputation.

Should I learn plain PHP before Laravel?

Generally yes. Understanding core syntax, OOP, and how PHP handles requests makes it much easier to understand what a framework like Laravel is doing for you, rather than treating its conventions as magic.

What's the difference between PDO and MySQLi?

PDO works with multiple database systems through one consistent API and supports named parameters, while MySQLi is built specifically for MySQL/MariaDB. Most new projects default to PDO for its flexibility, unless there's a specific MySQL-only feature they need.

How do I prevent SQL injection in PHP?

Use prepared statements with bound parameters through PDO or MySQLi instead of concatenating user input directly into a query string. This is the standard defense, and it removes the injection risk almost entirely when used consistently.

Laravel or Symfony — which should I learn first?

Laravel is generally considered more approachable for beginners, with more built-in conventions and a gentler learning curve. Symfony is more modular and configuration-driven, and many of its components (like the Console and HttpFoundation) are used inside Laravel itself.

How do I prepare for a PHP interview?

Be comfortable with OOP concepts like interfaces, traits, and dependency injection, understand common security pitfalls (XSS, CSRF, SQL injection) and how to prevent them, know your way around PDO and at least one framework, and be ready to explain how Composer and autoloading work.

Track complete

From syntax to a secure, database-backed application in a real framework — that's the core of what employers expect from a PHP developer. Keep building, and let Laravel, Symfony, or a plain-PHP project pull you toward the parts of the ecosystem you enjoy most.

Where next?

Keep exploring by domain or drill into a single skill

Browse by Domain

Role-based roadmaps like Backend, DevOps, and AI/ML Engineer.

Browse by Skill

Go deep on one tool at a time — Kubernetes, Terraform, Git, and more.