CDs are red, DVDs are blue, some can’t tell the difference, can you?

Here's the next in a series of explanations of why noobies are so easily confused by technology.

My dad recently received a video in the mail from someone he met during his travels to India. He wanted to share the video with me and asked me if I'd like to watch it. After I agreed, I asked what format the video was on. My dad replied that it was on CD but then paused and said, "Or maybe it's a DVD."

He then asked a very logical noobie question: "How can I tell if it is a CD or a DVD? What's the difference?"

I replied with this gem: "CDs are for audio, DVDs are for audio and video. But you can put a video data file on either a CD or DVD but you'll need a DVD player capable of playing data DVDs to play either the CD or the DVD."

The look on my dad's face forced this follow-up: "It's probably a DVD."

This seemed to satisfy my dad but it didn't satisfy me. I had to think harder about this. Presented a CD in someone's left hand and a DVD in that same someone's right hand, could a noobie tell which was which? Maybe. Maybe not. And to be honest with you, I might not be able to tell which is which either. I would probably check the coating on the back side of the disc but more than likely, I would deduce my answer from any writing I would hope to find on the disc.

There's probably some alternate universe somewhere where all CDs are red and all DVDs are blue but here on planet Earth, we'll just let the noobies keep guessing which is which.