Photographs are those things we used to buy before we had digital cameras.
I heard this definition at a recent conference on inkjet printing that I attended. I like it because there is a certain truth to this definition. I have a hard time calling a temporary image stored on a digital camera or cell phone a photograph. Somehow, a photograph sounds permanent and much of the time that is now not the case. This definition also highlights the change in imaging technology that continues to take place, with film sales declining to less than 10% of their peak sales.
Along the same line, it is certainly possible that my kids will define a photograph as those things that mom and dad put in scrapbooks before they had us. After all, they really don’t know what a non-digital camera is.