Google's Material Design guidelines are a series of recommendations from Google to assist developers in designing their applications, and to help introduce developers to changes and key points on how to best implement these guidelines, Google puts out details as part of their Material Design Spec on the web which goes through various steps and other bits of information on what's new and why each category matters. Each section also details things visually to give developers an example of what these changes may look like. The May 2016 release of the Material Design Spec goes through Material Motion, Growth & Communications, and Expansion Panels.
Motion is the first highlighted section, explaining that Motion is important because it shows what an app can do and how it's organized. One of the elements of motion is that it's responsive and is meant to have lots of energy, delivering a quick response to the user following their touch input. In addition to being responsive, motion should also have pinpoint accuracy. Google explains that motion is also natural, aware, intentional, and quick, and things should fit together cohesively, with customization having a consistent look and feel throughout the app. At each sub-section within the Motion category, Google displays short videos that demonstrate each point to give developers a better idea of how things appear.
When it comes to Growth & Communications, this section is mostly about explaining to the user what the app's capabilities are, from onboarding to help the user become familiar with the app UI to helping them discover the different features that the app provides. In this section, Google also explains that the first seven days should be all about onboarding the user and educating them on how to use the app, while the following 30 days and beyond should be focusing on feature discovery, so as to potentially show the user something that the app can do that they may have not yet tried. The last section, Expansion Panels, is focused on detailing creation flows that developers can utilize for light editing of various app components. Each section goes in depth about its respective focus, although Growth & Communications easily feels like the largest part, which is where developers may want to spend the most time reading.