Vue.js not being recognised with CDN-CodePudding

Hi I am currently learning Vue.js and I have an issue with it, I am calling Vue using a CDN.

I have followed instructions but it does not seem to be recognising that Vue exists.

   <!DOCTYPE html>
    <html lang="en">
    <head>
      <meta charset="UTF-8" />
      <meta name="viewport" content="width=device-width, initial-scale=1.0" />
      <title>Vue Basics</title>
      <link
        href="https://fonts.googleapis.com/css2?family=Jost:wght@400;700&display=swap"
        rel="stylesheet"
      />
      <link rel="stylesheet" href="styles.css" />
      <script src="https://unpkg.com/vue@3"></script>
  
      <script src="app.js" defer></script>
    </head>
    <body>
      <header>
        <h1>Vue Course Goals</h1>
      </header>
      <section id="user-goal">
        <h2>My Course Goal</h2>
        <p>{{coarseGoal}}</p>
      </section>
    </body>
    </html>

This is the simple js file It does not output the code from the Vue object.

Would really appreciate any help on this.
```
    const app = vue.createApp({
        data(){
        return {
            coarseGoal: 'This is the best',

        };
    }
    });
    app.mount('#user-goal');

CodePudding user response：

It should be Vue.createApp instead of vue.createApp.

Working Fiddle

const app = Vue.createApp({
  data() {
    return {
      coarseGoal: 'This is the best',

    };
  }
});
app.mount('#user-goal');

<title>Vue Basics</title>
<link href="https://fonts.googleapis.com/css2?family=Jost:wght@400;700&display=swap" rel="stylesheet" />
<link rel="stylesheet" href="styles.css" />
<script src="https://unpkg.com/vue@3"></script>
<body>
  <header>
    <h1>Vue Course Goals</h1>
  </header>
  <section id="user-goal">
    <h2>My Course Goal</h2>
    <p>{{coarseGoal}}</p>
  </section>
</body>