PHP learning resources
An easy-to-read, quick reference for PHP popular coding standards, links to authoritative tutorials around the Web and what the contributors consider to be best practices at the present time.
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This is a list of language features and functions added or removed in recent PHP versions. It is not an exhaustive reference.
The PHP Standard Recommendation is a PHP specification published by the PHP Framework Interop Group. Similar to Java Specification Request for Java, it serves the standardization of programming concepts in PHP. The aim is to enable interoperability of components and to provide a common technical basis for implementation of proven concepts for optimal programming and testing practices. The PHP-FIG is formed by several PHP frameworks founders.
Each PSR is suggested by members and voted according to an established protocol to act consistently and inline with their agreed upon processes.