iphoto question

if I were to import pictures from my "photos" folder on my hard drive onto iphoto, does that create duplicate images? If I were to delete photos from iphoto, would that delete the image from the original source?

If you have photos in a folder outside of iPhoto library, and you import them into iPhoto, yes, you will have duplicates. You can delete the original folder and still have your photos in iPhoto. If you delete from iPhoto (using the app), it will not delete from the other folder. They are two separate things.