Several years have passed since the time when I tried to understand Magento development. At that time, Magento was something unreal and very difficult for me. I tried over and over again; I did a lot of mistakes. One day I woke up and bingo!!! It was really amazing to understand how it works. Well, in this article I would like to talk about the caveats that were, most likely, encountered in development by a lot of my fellow PHP developers.