$(function () {
  // Create a model class.
  const TodoItem = Backbone.Model.extend({
    // RESTful web service, RoR flavor.
    urlRoot: '/server/todos'
  });
  // Create a model instance to load it by ID.
  const todoItem = new TodoItem({ id: 1 });

  // Access the server at /server/todos/1 (urlRoot + '/' + item.id).
  const x = todoItem.fetch({ async: false });

  // Manipulate attributes.
  const description = todoItem.get('description');
  todoItem.set('status', 'complete');

  // Save on server.
  todoItem.save();

  // Create a view class.
  const TodoView = Backbone.View.extend({
    render: function () {
      const html = '<h3>' + this.model.get('description') + '</h3>';
      $(this.el).html(html);
    }
  });
  // Create a view instance.
  const todoView = new TodoView({ model: todoItem });
  todoView.render();
  $('#app').html(todoView.el);
});