Well in bitcoin we can trade it offline if you know the person that you'll trade with your coins. Otherwise, they are the same that way but depending on situation but most of the time bitcoin is being trade by people who doesn't know who they are trading to. And that's the best difference of these two, bitcoin = digital, fiat=physical.
True bitcoin can be exchange anytime any where i have friend who b uy it from me every month he want to stake 0.1 btc in wallet as his ensurance found. I have some local dealers that i know that do the same with some 5% fee, so both are in one way money or mean to pay/purchase some good or something else.
In the way of things but this is good both are good both are used and bitcoin will be future of everything in next several years.