BitInfoCharts shows a side-by-side comparisons between all the currencies. It includes the price, market cap, total outstanding amount in the market.
Bitcoin investors just do not understand the concept of money. A currency that is not backed by any commodities will fluctuate as high as it can go and drop to worthless in seconds. As China's biggest online marketplace, Alibaba Group Holding Ltd's Taobao banned the sale of bitcoins due to government crackdown, the price of Bitcoin instantly dropped. The lack of transparency and consistency only will increase bitcoin's mistrust and Bitcoin's market volatility. in 2011, the value of one Bitcoin rapidly increase from US $0.30 TO US$31; in February 2011, quickly falling back down to US $2.
At present the exchange price of a Bitcoin is extremely volatile, which many question about its ability to function as a currency, however others indicated that it's a necessary "growing pain" in such a new technology, and that Bitcoin needs to grow to achieve stability.