For above and many more reasons, Yii core files should be kept **outside** project directory and anywhere outside any web-accessible directory. I.e. if you keep your project files in Apache's _httpd_ directory, it is wise to create a new dir (called _yii_, _frameworek_ or smth. like that) in the same level of dirtree (inside Apache main folder, **not** in _httpd_ dir!) and put Yii core files there. If you do that, you have to include Yii folder in _Include Path_, as it is written above.
#### Usage:
- Typing suggestions: Ctrl-Space
- Show Function parameters: Ctrl-P
- Comment your own code with PHPDoc style. [Here's a good example](http://manual.phpdoc.org/HTMLSmartyConverter/HandS/phpDocumentor/tutorial_sample2.pkg.html).