Since DOM elements are arranged in a hierarchical structure, scopes mimic that hierarchy. This means that each scope has a parent scope up until the parentless object called the root scope. This is important, because aside from referencing their own model, scopes can also inherit the model of their parent scopes. So if a model property cannot be found in a current scope object, Angular will look for this property in the parent scope, and so on, until it finds the property or reaches the root scope.
angular looks for properties in scope hierarchycally
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