I save everything that I don't delete on an external HD. I also burn copies to 2 different DVD's. This includes all of the RAW files, and any images that I converted to other formats.I take one set of DVD's to work and leave them there. That way if the house burns down, I still have a copy. I don't use anything special for my DVD's. I buy a spool of 50 or 100 from a big box store. I need to get into a better habit of backing up my images. I don't do it nearly as often as I should.