Sometimes you need observables purely for the visual and they got no connection to the view-model.
Using the vars
property new observables can be added to the page context.
<div data-bind="page: {id: 'start', vars: {lorem: 'ipsum'}}"> <input type="text" data-bind="value: lorem, valueUpdate: 'afterkeydown'"/> <div data-bind="text: lorem"/> </div>