Most applications will have one or two sidebars and often you want to control the content that should appear in the sidebar based on the action. For example you will want to show something different on the homepage as opposed to some view page. While achieving this you generally also want to avoid putting the layout into each view, as that would mean if you wanted to change the layout (e.g. put the sidebar on the left instead of the right or do some funky layout which requires an additional div tag to be added) you'd have to go through every view, which does not achieve good code re-use. It is also bad practice to have lots of if statements in column2 layout just so that you can generate the sidebar correctly.
Here is a step by step To-Do list for Yii beginners. The list is an advice of what tutorials and documentation you can walk through to get a full understanding of the Yii Framework. These can be a help to learn Yii.
The Definitive Guide introduces the fundamentals of managing URLs in a Yii application. In this tutorial, we introduce a practical technique that can quickly turn your application into using search-engine-friendly URLs.
The purpose of this post is to let anyone quickly find how to accomplish a configuration task, and list here all the posibilities of the config.php file and also link to pages that explain how is each thing implemented.