That probably happens because your hard disk is formatted NTFS and your USB-stick is formatted FAT32.
I don't think it harms, but why not try? Just copy one picture to the USB-stick, copy it back to another location on your hard disk and compare the original and the copy. What do you see?
If unhappy with the result, change the USB-stick to NTFS and everything will be fine. But you can't use it in your Mac then anymore. Or use another USB-stick or an external drive, that already is NTFS.
By the way, do I understand correctly you don't yet have a backup? Then you are lucky you didn't lose those pictures already in the past. Better start a regular backup for things you don't want to lose.
Kees
Hi, I'm not very tech minded and wondered if anyone could help. I'm trying to take all my photos off my laptop so I can set it to factory settings. The problem is when I copy/send them to my usb stick it says I can't transfer the properties of the folder/photos. What does this mean and do I need the properties to save a photo?

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