I've had a Mac for about a year now and while I know what time machine does I'm not too sure how it works. I know when I got a new Mac I was able to connect my 3tb hard drive and restore my back up which was super easy I might add. My question is does time machine back up your computers current state or continue to add content to the back up. Like if I delete photos from iPhoto then back up do those photos get deleted from the back up as well? Do I need to manually create a photo folder on my 3tb sea gate hard drive to make sure my photos are saved?