A collection of 4 similar PHP login / authentication scripts for different use cases.
From simple one-file login with SQLite flat-file database to professional Composer-using MVC application.
Built with the official PHP 5.5 password hashing functions (100% backwards compatibility pack for PHP 5.3 and PHP 5.4 included).
Clean, modern, future-proof, documented, commented, object-oriented and fits the PSR-1/2 coding guidelines.

OpenID Connect is an interoperable authentication protocol based on the OAuth 2.0 family of specifications. It uses straightforward REST/JSON message flows with a design goal of “making simple things simple and complicated things possible”.  It’s uniquely easy for developers to integrate, compared to any preceding Identity protocol.