A DVD is an example of a physical medium. It'd be better if you had them backed up somewhere (your DVDs, perhaps, but it's not technically digital) as well as in the "cloud" backed by a massive corporation that guarantees the safety of your memories. If you don't trust them because they may fold, you can also back them up on an external hard drive. If your preferred option of viewing pictures is in a scrapbook or just physical photographs, then by all means print them. But what happens when your one-time quality print gets destroyed and you have no digital?