http://files.coinmarketcap.com.s3-website-us-east-1.amazonaws.com/static/img/coins/200x200/bitcoin.png

The value of the bitcoin currency is defined by market forces. That is to say: the value of a bitcoin depends on its supply and demand.

Currently about 15 million bitcoins are negotiated per month. The main exchange houses are btchina, okcoin.com, bitfinex and Bitstamp. And currently more than 80% of bitcoins are traded in RMB (yuan).