You now know all the techniques to find, manipulate, and style web page elements using Dart code to change the user interface, and you can respond to the events that take place on the page. You have learned how to change the CSS properties in DOM in order to move game objects, how to draw on a canvas to develop game screens, and how to build a complete game project. We found that it is advisable to develop a project in a spiral way, building upon the previous spirals as the project gets more functionality. The different entities are represented by classes; in this way, our project is naturally modularized. In the next chapter, we will focus on the web page as a way to show, gather, and validate data, because this is what we will need to do in business apps.