Weird folder-names, imho, are to avoid name duplication.
Each time you edit the original file, the asset manager checks for a new version of it and automacally copies new file to the appropriate asset folder.
It’s better if you put your CSS and javascript files in another folder… so that the assets folder is just for Yii usage… this way when you upgrade Yii, for example, you can just empty the assets folder… if there would be some other scripts that your project needs… you would need to pay attention to not delete those scripts…
Thanks mdomba. And the next question: So during moving files in the live server, do we need to move these folders too or Yii will automatically does it?
You need to create the assets folder… and set its permission as writable by the web process… you don’t need to upload the content of this folder as Yii will populate it as needed…