An Introduction to PHP Standard Recommendation (PSR)

Once upon a time, at a conference, the lead developers from a selection of frameworks sat down in the same room and agreed some standards for all their projects to use. The aim was to make PHP frameworks and libraries easier to combine for users. That is when php-fig: the PHP Framework Interop Group was born. This group of awesome individuals oversee the PHP Standards Recommendations (PSRs).

PSR-2 and PSR-12: Why We Need Standards and How to Apply Them – Quick Admin Panel

Evolution of PHP and Its Future

A Guide to Creating a PSR-4 Compatible WordPress Plugin - DLX Plugins

Standardization in web projects - BitBag

ExpressionEngine Adopts PSR-12, Blog

Introduction to PSR-14 & Event Dispatching Unification - Speaker Deck

PSR — The PHP Standards Recommendations Guide, by Alexandre Daubois

Intro To PSR (PHP standards recommendations), by Moath Obeidat

Introduction to the PHP Standard Recommendation – PSR-1, Independent Software

PHP Professional Toolkit