var data = {
 name: "erik",
 getName: function() {
  return this.name;
 },
 setName: function(name) {
  this.name = name;
 }
};

<form id="demo">
 <!-- text -->
 <p>
 <input type="text" v-model="msg">
 {{msg}}
 </p>
 <!-- checkbox -->
 <p>
 <input type="checkbox" v-model="checked">
 {{checked ? "yes" : "no"}}
 </p>
 <!-- radio buttons -->
 <p>
 <input type="radio" name="picked" value="one" v-model="picked">
 <input type="radio" name="picked" value="two" v-model="picked">
 {{picked}}
 </p>
 <!-- select -->
 <p>
 <select v-model="selected">
  <option>one</option>
  <option>two</option>
 </select>
 {{selected}}
 </p>
 <!-- multiple select -->
 <p>
 <select v-model="multiSelect" multiple>
  <option>one</option>
  <option>two</option>
  <option>three</option>
 </select>
 {{multiSelect}}
 </p>
 <p><pre>data: {{$data | json 2}}</pre></p>
</form>

new Vue({
 el: '#demo',
 data: {
 msg  : 'hi!',
 checked : true,
 picked : 'one',
 selected : 'two',
 multiSelect: ['one', 'three']
 }
})

<!-- synced after "change" instead of "input" -->
<input v-model="msg" lazy> 

<input v-model="age" number>

<select v-model="selected" options="myOptions"></select>

[
 { text: 'A', value: 'a' },
 { text: 'B', value: 'b' }
]

<select>
 <option value="a">A</option>
 <option value="b">B</option>
</select>

[
 { label: 'A', options: ['a', 'b']},
 { label: 'B', options: ['c', 'd']}
]

<select>
 <optgroup label="A">
 <option value="a">a</option>
 <option value="b">b</option>
 </optgroup>
 <optgroup label="B">
 <option value="c">c</option>
 <option value="d">d</option>
 </optgroup>
</select>

<input v-model="msg" debounce="500">