What are the various Helper classes provided by the Yii ? There are several classes provided by framework: ArrayHelper Console FileHelper Html HtmlPurifier Image Inflector Json Markdown Security StringHelper Url VarDumper What is difference between Component and and Object? Classes of the Yii framework usually extend from one of the two base classes yiibaseObject or yiibaseComponent. These classes provide useful features that are added automatically to all classes extending from them. The Object class provides the configuration and property feature. The Component class extends from Object and adds event handling and behaviors. Object is usually used for classes that represent basic data structures while Component is used for application components and other classes that implement higher logic. What does Yii stand more? Yes it is