SOURCE

> Uncaught ReferenceError: Vue is not defined

var app = new Vue({
  el: '#app',
  data: {
    message: 'message'
  },
  beforeCreate() {
    console.log('beforeCreate')
  },
  created() {
    console.log('created')
  },
  beforeMount() {
    console.log('beforeMount')
  },
  mounted() {
    console.log('mounted')
  },
  beforeUpdate() {
    console.log('beforeUpdate')
  },
  updated() {
    console.log('updated')
  },
  activated() {
    console.log('activated')
  },
  deactivated() {
    console.log('deactivated')
  },
  beforeDestroy() {
    console.log('beforeDestroy')
  },
  destroyed() {
    console.log('destroyed')
  },
})

<div id="app">
  <h1>
    {{message}}
  </h1>
</div>