Obviously I'm a newbie to Mac - had it all of two days now and am trying to understand the basics of IPhoto - which seems like a really cool program. My question is this: I store all my photos on an external server / hard drive accessible to multiple computers with our family. When I import them into IPhoto, am I actually copying them onto my Mac (thereby having two copies of my photos - one on the external HD and one on my Mac) or is it like Google's Picasa that just stores thumbnail info for organizing, etc? Also, I like to use Adobe Photoshop Elements to edit, play with the photos, and thus, when I save a changed copy of the photo to this external hard drive (while keeping the original), do I then need to import the copy over to IPhoto or does IPhoto have a scanning feature similair to Picasa that will scan the drive and pick up new additions? Thanks!