The ".vue" File

You can learn more about ".vue" Files in this Article from the official Docs: http://vuejs.org/guide/single-file-components.html

Learn more about the render()  method in another Article in the official Docs: http://vuejs.org/guide/render-function.html

Finally, it's important to be aware of the fact, that you can also load your App.vue File (your main Component/ Instance) via the following two Ways (Alternatives to render() ):

1) Using the ES6 Spread Operator (for that, you need to add babel-preset-stage-2 as a Dependency and to your .babelrc File):

npm install --save-dev babel-preset-stage-2 

.babelrc:

{
  "presets": [
    ["es2015", { "modules": false }],
    ["stage-2"]
  ]
}


import Vue from 'vue'
import App from './App.vue'

new Vue({
  el: '#app',
  ...App
});


2) Using mount() :

Also install the stage-2 preset as described above.

import Vue from 'vue'
import App from './App.vue'

const vm = new Vue({
  ...App
});

vm.$mount('#app');


The CLI

Learn more about the CLI here: https://github.com/vuejs/vue-cli

Local CSS / Sass Files and CLI Templates

The webpack-simple template doesn't support local CSS or Sass files, because no CSS loader is set up.

Use the webpack template (not webpack-simple) to get this functionality: https://github.com/vuejs-templates/webpack