I'm traveling at the moment, so I don't have access to my iTunes Mediathek library with all my songs etc. However, my iPhone 6 is having some trouble and I want to reset it and then restore from a backup. What happens if I create a backup and restore my iPhone from this backup, at someone else's Mac which does not have my iTunes library? Are all my songs included in this backup? I know that photos, app data etc. is included but I'm worried about everything related to my iTunes library like music.