If your background is PHP,you're probably used to putting the code under the Web Server's document root(in a place such as /var/www).With Django, you don't do that.It's not a good idea to put any of the python code within your Web server's document root,Because in doing so you risk the possibility that people will be able to view your code over the Web.That's not good for secure applications.
Always put your python code in some directory outside of document root.
