An ObservableCollection is a dynamic collection of objects of a given type. Objects can be added, removed or be updated with an automatic notification of actions. When an object is added to or removed from an observable collection, the UI is automatically updated. This happens because, when binding to an observable collection, WPF automatically adds a CollectionChanged event handler to the ObservableCollecion’s events.
The ObservableCollection class exists in the System.Collections.ObjectModel namespace.
I have a window with a Button, two TextBoxes and a ListView and each time you click the Button the text of the TextBox is added to the collection and the ListView is updated automatically.