The App Bar is part of the set UI composition of every Mews screen . The App Bar is a collection of components shared by all products within a platform. It provides a common set of interaction patterns that persist between and across products.
The App Bar is the foundation for navigating and orienting your user to the UI. The UI Top Nagivation can be used by itself or combined with the left side navigation or right panels for more complex UI navigation.
The UI Navigation is made up of three components—the Top, the left, and the right side panel. All three can be used independently, but the components were designed to work together.