Vue 2.0 Hello World

HTML

<script src="https://unpkg.com/vue/dist/vue.js"></script>

<div id="app">
    <select v-model="pr">
      <option value="1">one</option>
      <option value="2">two</option>
      <option value="3">three</option>
      <option value="4">four</option>
    </select>
  <div>
    {{ pr }}
  </div>
</div>

JavaScript

new Vue({
  el: '#app',
  data: function () {
    return {
      pr: 1
    };
  },
})