Canvas components make it easier to build reusable controls, such as navigation menus and dialogs.

The ‘master’ / ‘instance’ behavior makes it easy to reuse them as building blocks inside the app or shared between apps.

By creating a component library, app makers easily share and update one or more components with other makers.

Component libraries are containers of component definitions that make it easy to:
Discover and search components.
Publish updates across environments.
Notify app makers of available component updates.