Check out a free preview of the full Advanced Ember 2.x course:
The "UI State" Lesson is part of the full, Advanced Ember 2.x course featured in this preview video. Here's what you'd learn in this lesson:
Michael introduces the concept of State UI, which are short pieces of information for the user. Examples of UI States are an accordion expansion, saving a user's scroll position, or notifying if a friend "is typing..." a message in a chat application.