Thanks. Does that mean that I can delete all photos outside of the iPhoto Library, because iPhoto has created a copy of all these inside the iPhoto Library?

As long as you see the photo in iPhoto, it should be safe to delete the photo outside of the iPhoto library folder.

I tell people to think of iPhoto as they do iTunes. No one goes in to the iTunes Music folder to play their music or to delete them, we open iTunes, play the song or do whatever else we need to with it. Think of iPhoto the same way. When you need to find a photo, open iPhoto and use it from there. You should be able to do most things from iPhoto: email pictures, burn back ups, upload to .Mac, etc. I never look in my iPhoto folder, it would take me much longer to find a photo.

What about if I, say, wanted to upload photos onto facebook? I find that the upload program built into facebook is a hassle as it sorts the photos into modified photos and the originals