<head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title></title> <script src="js/jquery-1.11.1.min.js"></script> <script src="js/knockout-3.3.0.js"></script> <script> var viewModel = { myMessage: ko.observable() }; var viewModel1 = { price: ko.observable(24.95) }; viewModel1.priceRating = ko.pureComputed(function () { return this.price() > 50 ? "expensive" : "affordable"; }, viewModel1); $(function () { viewModel.myMessage("Hello, world!"); viewModel1.price(51); ko.applyBindings(viewModel, $("#no1")[0]); ko.applyBindings(viewModel1, $("#no2")[0]); }) </script> </head> <body> Today's message is: <span id="no1" data-bind="text: myMessage"></span> <br /> The item is <span id="no2" data-bind="text: priceRating"></span>today. </body>