I found it very helpful to specify, for my own, use, exactly which entities I meant.
"Photo" has no fixed meaning in Aperture.
"Original" is the name Aperture uses to designate the digital Image files you import into an Aperture Library.
The program Finder keeps files in folders. These are different from the folders that Aperture shows in your Library. In fact, there is no relation at all between the Folders you create in Aperture to organize your Images, and the folders your create in Finder to store your files.
Exporting creates new image-format files from Images in your Library. You don't need to create these files if all you want to do is move your Originals to a location outside your Library. Use -- as Frank says -- "File➞Relocate Originals".
Your Library shows your Images.
Each Image has a Version and an Original.
Your Originals are never altered.
The first Version is usually null (the Version says, in effect, make no changes to this Original).
The Version (a text file of instructions) is always stored inside your Aperture Library.
Your Originals can be stored inside the Aperture Library, or outside.
Originals stored inside the Aperture Library are called "Managed Originals".
Originals stored outside the Aperture Library are called "Referenced Originals".
HTH.
--Kirby.
