For all of the Joomla! components, code empowering the backend portion is kept away from the frontend code. In some instances, the backend may use certain files from the frontend (and vice versa), but in general the two are separate. Security is enhanced as you are less likely to slip the administrative functions into the frontend code. This is an important distinction as the frontend and backend are similar in structure.

The following folder diagram shows the Joomla! root with the administrator folder expanded:

Note that the administrator folder has a structure similar to that of the root folder. It is important to differentiate between the two. If you accidently place your code in the wrong folder, it will fail to execute until you move it.