The whole idea of Apple Photos is to create a safe, secure library of pictures that can be called up and exported on demand, customized for their particular destination.
As a lover of photos in general, and the caretaker of my own family picture library, it tears me apart whenever I hear someone caught in that terrible place. That one where their iPhone is crushedsoakedloststolendeadgone and it's the only place their honeymoonnewbornlatefatheroldfriend's photos exist.
In 2002 amateur photographers were thrilled by how they could make photo books and order prints without ever leaving iPhoto. True to the Apple brand, the books were easy to create and the quality was as good or better than comparable books from other printers. You didn’t have to export pictures to another bookmaking app or create an account with another company. People made Apple photo books for all kinds of events and occasions.
Probably the first thing you'll hear about from a professional photo organizer (yes, it's a thing) is that your digital photos need proper digital information. One of those information fields is for "description" or "caption" and, as luck would have it, the latest iOS upgrade (iOS 14) lets you easily add a description to the image right on your iPhone.
