Yii is a high-performance PHP framework to develop modern web apps quickly. It uses the MVC pattern and it allows you to use it for full-stack development through its ready-to-use features, including multi-tier caching, RESTful API support, and query builders. Focused mainly on high performance, Yii helps you write simple and elegant syntax to ensure your applications always run at the top of their game.

Yii is an open source, object-oriented, component-based MVC PHP web application framework. Yii is pronounced as "Yee" or [ji:] and in Chinese it means "simple and evolutionary" and it can be an acronym for "Yes It Is!".