Let's recap

• Angular separates updating the application model and updating the view.
• Event bindings are used to update the application model.
• Change detection uses property bindings to update the view. Updating the view is unidirectional and top-down. This makes the system more predictable and performant.
• We make the system more efficient by using the OnPush change detection strategy for the components that depend on immutable input and only have local mutable state.