The Data Binding Library is an Android Jetpack library that allows you to bind UI components in your XML layouts to data sources in your app using a declarative format rather than programmatically, reducing boilerplate code.
Congratulations! You completed the codelab, so you should know how to create Data Binding layouts, add variables and expressions to it, use observable data, and make your XML layouts more meaningful with custom attributes via custom Binding Adapters.