Application Instance

Every Vue 3 application starts by creating a new application instance using the createApp function. An options object is passed to the createApp function to configure the root component. We will discuss what options can be included in this object later in the course.

const app = Vue.createApp({ /* options */ })

An application needs to be mounted to a DOM element using the mount function. The mount will provide access to the root component.

<body>
  <div id="app"></div>
</body>

const app = Vue.createApp({ /* options */ })
const vm = app.mount('#app')

NOTE

The createApp function and the application instance are new to Vue 3 and will not work in previous versions of Vue. Likewise, creating a Vue Instance, a common practice in Vue 2, does not work in Vue 3.

# Application Instance

Application Instance