In this lesson, we are going to include the necessary assets for the functionality and styles of the Ionic directives we will include in our app.
Good question! In short, no, Ionic doesn't automagically add local versions of CDN files. As outlined here, you should only use files from a CDN for demo/dev purposes or if your application will rely heavily on the internet. The app for this lesson falls into the former category, which is why we went with files from a CDN.