Where are JS libraries hosted?
lib/slideshow.jsif it was inside a folder named
lib. When you're working locally, make sure you open up your browser's network panel to make sure it found all the local resources like your JS files and CSS files. If the browser couldn't find a resource, you'll see a 404, and you can debug the URL and file location.
https- that means it’s a secure URL. We only allow you to bring in secure resources in Khan Academy webpages, and that's a best practice in web development. Not all servers have SSL enabled yet, however, so you may sometimes have to start URLs with
httpin your projects.
cdn.rawgit.com, and it's an example of a "CDN" - a "content delivery network." CDNs are optimized for serving static files like JS libraries and serving them very quickly. There are a few big CDNs that host multiple JS libraries (like Google's CDN and cdnjs), and there are some libraries that have their own dedicated CDN.