Web and technology
PSR
Abbreviation for PHP Standard Recommendation
In short and in plain language
PSR is a shared rule for programs written in PHP.
Each rule has a number.
PSR-3, for example, says how programs write messages to a log.
Definition
PSR stands for PHP Standard Recommendation, a numbered recommendation of the PHP Framework Interop Group (PHP-FIG) for shared interfaces and conventions in PHP. PSR-3, for example, describes a common logger interface with eight log levels from debug to emergency, so that frameworks and libraries use the same levels.