vue.js - Bind Vue on body or others element

Question

I've seen many times Vue instance is bind on body tag. Other times this is bind on a div id

I'm asking when i should use body tag or an id tag (that limit the scope of the Vue instance).

Two examples:

new Vue({
  el: 'body'
});

OR

new Vue({
  el: '#a-div'
});

Answer 1

You should never use the body tag. In fact, it raises a warning to use the body tag.

Added a warning when mounting the root instance to body or html. This is no longer recommended in 2.0.

This is from the release notes, anyways it's incorrect, it raises an error.