Price is a result of aggregate decisions of big players, which use approx. common relevant information that may affect:
1. Economy performance of respective currency.
2. Central Bank decisions.
3. Political decisions.
4. Causing uncertainty
The faster you price in crucial information (analyzing and understanding how market agents' expectations change), the more is your edge
Sometimes there is a chain reaction, for example insignificant piece of info (A) affects B, then crucial for markets C = there we have new expectations forming. If you are shrewd enough to build this logical chain correctly, then you gain edge.
Remember that price is a last result of everything that happens. There are desk guys that click buy and sell and cause the price to move. Price is not the reason for future price changes.