Storing photos on the iMac.
If I download photos to a second photo library, not the system library, are they stored there on the Computer hard disc? Are they "referenced" photos? Then if I move to the system library, they will be stored in the cloud? And where is My Photo Stream? it seems not always there, is it the same as Recents?
iMac 21.5" 4K, macOS 10.15