Hi Dan,
App42 File Storage usage CDN network to store and access binary/media files. CDN (Content Delivery Network) is distributed access network across the globe for accessing the files over HTTP. This provides faster access of file to the user as it is being served by near by CDN access location. App42 CDN is located on 51 access location across the globe. Once you upload any file you will get an HTTP end point URL for that file pointing to CDN network. If you request that file in browser, it will be fetched from near by access location for faster response.
Let me know if it answers your query.
Thanks
Ajay