What is using a JS framework through a script-tag called?

For example using: <script src='https://vuejs.org/js/vue.js'></script>. Ik you can use bootstrap like this too. Is there a name to this design-pattern? I don't know exactly what to google to learn more about this. I'm looking for resources for best practices to making a framework like this. I'm guessing they are serving the dist file on this end point https://vuejs.org/js/vue.js. So when you import it they have full access to your Dom structure? and can interact with other parts of your app?