Bootstrap (http://getbootstrap.com) is popular and very useful. It changes the way of building UIs for web applications. As you will see when we implement the UI, Bootstrap can boost our productivity by providing features that cover most parts of UI development. It is highly customizable, allowing us to create different themes. In this section, we will learn how to import Bootstrap into a Vue application and use it to build the register page. We will also change webpack's configuration to keep the styles of Bootstrap in a separate .css file.