A roadmap to become a senior PHP developer
Basic syntax
Documentation
PHP: Basic syntax - Manual
Variables
Documentation
PHP: Variables - Manual
Constants
Documentation
PHP: Constants - Manual
Exceptions
Predefined Variables
Documentation
PHP: Predefined Variables - Manual
Expressions
Documentation
PHP: Expressions - Manual
Classes and Objects
Control Structures
Documentation
PHP: Control Structures - Manual
Operators
Documentation
PHP: Operators - Manual
Functions
Documentation
PHP: Control Structures - Manual
Namespaces
Article
PHP: Namespaces - Manual
Errors
Documentation
PHP: Errors - Manual
Types
Documentation
PHP: Types - Manual
Documentation
JSON:API — A specification for building APIs in JSON
JSON
Documentation
JSONArticle
JSON - Wikipedia
Article
Design Patterns | Object Oriented DesignArticle
Design Patterns - Wikipedia
PHP: OOP basics
Documentation
PHP: The Basics - Manual
Design Patterns
Documentation
Design Patterns PHP 1.0 documentationDocumentation
The Catalog of Design Patterns
Article
What are relational databases? | HowStuffWorksArticle
What Is a Relational Database | Oracle
SQL Syntax
Database Normalization
Nginx
Documentation
nginx documentationDocumentation
DevDocs - nginx documentation
Client Server Architecture
Article
Client–server model - WikipediaArticle
What is Client-Server Architecture?Article
Client-server Architecture
HTTP header
Article
List of HTTP header fields - WikipediaArticle
HTTP headers - HTTP | MDN
HTTP body
Article
HTTP message body - Wikipedia
PHP Interface: Serializable
Documentation
PHP: Serializable - Manual
PHP interfaces: Iterator
Documentation
PHP: Iterator - Manual
PHP Interface: ArrayAccess
Documentation
PHP: ArrayAccess - Manual
PHP interface: Traversable
Documentation
PHP: Throwable - Manual
Wordpress for programmers
Documentation
Developer Documentation « WordPress Codex
Composer
Documentation
ComposerArticle
Introduction - Composer
PHP framework laravel
Documentation
Official documentation for Laravel
Yii
Article
Yii - WikipediaDocumentation
Yii PHP Framework
Symfony
Documentation
Symfony, High Performance PHP Framework for Web DevelopmentArticle
Symfony - Wikipedia
Article
HTML StandardArticle
HTML Tutorial
HTML basic tags
Tutorial
HTML - Basic Tags - TutorialspointDocumentation
HTML Reference
CSS
Documentation
CSS TutorialArticle
Cascading Style Sheets - WikipediaArticle
CSS: Cascading Style Sheets | MDN
Documentation
Git - Reference
To see a interactive roadmap click on picture