All of them (fiat money, gold, dollar, yuan and other currencies) are used for trade stuff.
Flash back, i really salute with satoshi nakamoto who can turn their "digital stuff" into real money. (Satoshi Nakamoto is a group name, not only stand for 1 people)
Fiat money is crap.
Gold used to be currency, but now we have better technology. You are not using washing board instead of washing machine? Do you make a campfire in your room or you use an owen?
Bitcoin is superior technology and it is the real money in 21 century.
40% Bitcoin and 60% Altcoin.
No thats not true, thats the lame excuse gold bugs say to demonize bitcoin as money.
We already have thousands of altcoins, and bitcoin makes up 89.022% of the total cryptocurrency sector:
Total Market Cap: $ 5,308,580,616
Bitcoin Market Cap: $ 4,725,833,968
http://coinmarketcap.com/all/views/all/