Yes, it is! Yii is a fast, secure, and efficient PHP framework. Flexible yet pragmatic. Works right out of the box. Has reasonable defaults.

The Definitive Guide to Yii 2.0 and the API Documentation are available for offline browsing. Below you will find the download packages including the HTML files of Guide and API Documentation as well as …

The Definitive Guide to Yii 2.0 Introduction About Yii Upgrading from Version 1.1

Yii is a high performance, component-based PHP framework for rapidly developing modern Web applications. The name Yii (pronounced Yee or [ji:]) means "simple and evolutionary" in Chinese.

You can install Yii in two ways, using the Composer package manager or by downloading an archive file. The former is the preferred way, as it allows you to install new extensions or update Yii by simply …

Yii provides a whole set of tools to simplify the task of implementing RESTful Web Service APIs. In particular, Yii supports the following features about RESTful APIs: Quick prototyping with support for …

Yii Framework 3.0 API Documentation Container & Proxy di factory definitions container-proxy proxy injector

There are instructions in the manual as to how to configure Yii to use i18n, but little information all in one place on how to fully integrate it into the bootstrap menu.

Yii 2.0 权威指南 介绍（Introduction） 关于 Yii（About Yii） 从 Yii 1.1 升级（Upgrading from Version 1.1）

Yii 3 is the second major rewrite of the Yii framework. Originally started in the 2.1 branch, it was later decided to switch to the 3.X series because of all the backward compatibility breakage.