I have backed up my songs by copying the iTunes folder to my external hard drive. But when I add new albums or purchase songs from the iTunes store, I understand that the iTunes folder gets updated. How do I sync those new songs or album additions to my external hard drive?
MacBook Pro
See: Backup your Library and media files here > About AirPrint - Apple Support
I think the Airprint is a mistaken link.
You need to copy your iTunes folder each time you want to back it up. If you use Time Machine or another incremental updating utility, instead of having to copy the entire folder the utility will review what has changed and update the backup to reflect only the changes. This can be a lot faster than copying the entire folder each time.
How do I sync my new iTunes purchases to my external hard drive
