Forex (Foreign Exchange) or Foreign Currency is a type of transaction that trades a country's currency against another country's currency in order to gain profit from different currency values. Equality of stock and Bitcoin can also be found in the world of Forex where the traders take advantage of the opportunity to buy foreign currency when the price is still cheap and resold at higher prices.
The price movements of those three things are influenced by supply-demand, and people can predict the direction of price movements by technical analysis methods (looking at charts and patterns of past price movements) or fundamental (looking at the intrinsic value or company circumstances). Using any analytical method, no prediction can be 100% accurate because stock prices, Forex, and Bitcoin may change at any time when unexpected things happen. For example in the world of Forex: when 9/11 occurs, the USD rate falls because everyone estimates that the event will affect the weakening of the USD. This incident caused many market players to sell USD so that finally the USD rate really dropped dramatically.
With an average daily volume of US $ 2 trillion, the Forex Market is 46 times larger than all stock market combined and is, therefore, the most liquid market in the world. Compared to Forex, the Bitcoin market is still a small market so Bitcoin prices tend to change (5-7 times more volatile than Forex) when a party buys or sells Bitcoin in large quantities.
