In this chapter, I explore how to expand your knowledge of simple widgets so it covers the full canvas of controlling your overall application and activity layout and design. I use Android layouts as the definition-based way of describing how to organize and display all of the widgets and other UI artifacts that comprise your user interface. In order to understand how layouts work, you need to think of layouts as containers. A layout stores all of the widgets and their attributes so that they are ready to be used, just like ingredients in kitchen containers. The widgets I introduced in Chapter 5 are fine, but as soon as you want two or more widgets on a screen, it becomes increasingly cumbersome to manage each one—each has its own position, spacing, and inter-widget relationships—if you attempt to manage each individually. You have already seen a hint of how managing groups of widgets makes your life easier—through the RadioGroup element, which allows the aggregate control of multiple RadioButton widgets.