This depends on how liquid the currency is, or how much of it is being bought and sold at any one time. The most liquid currency pairs are the ones with the most supply and demand in the Forex market, and this supply and demand is generated by banks, businesses, importers and exporters, and traders. Major currency pairs tend to be the most liquid, with the EUR/USD currency pair moving by 90-120 pips on an average day.
Economic numbers: While economic numbers can certainly reflect economic policy, some reports and numbers take on a talisman-like effect: the number itself becomes important to market psychology and may have an immediate impact on short-term market moves. "What to watch" can change over time. In recent years, for example, money supply, employment, trade balance figures and inflation numbers have all taken turns in the spotlight.

"Buy the rumor, sell the fact": This market truism can apply to many currency situations. It is the tendency for the price of a currency to reflect the impact of a particular action before it occurs and, when the anticipated event comes to pass, react in exactly the opposite direction. This may also be referred to as a market being "oversold" or "overbought".[75] To buy the rumor or sell the fact can also be an example of the cognitive bias known as anchoring, when investors focus too much on the relevance of outside events to currency prices.
Second, since trades don't take place on a traditional exchange, you won't find the same fees or commissions that you would on another market. Next, there's no cut-off as to when you can and cannot trade. Because the market is open 24 hours a day, you can trade at any time of day. Finally, because it's such a liquid market, you can get in and out whenever you want and you can buy as much currency as you can afford.
Basically, the Forex market is where banks, businesses, governments, investors and traders come to exchange and speculate on currencies. The Forex market is also referred to as the ‘Fx market’, ‘Currency market’, ‘Foreign exchange currency market’ or ‘Foreign currency market’, and it is the largest and most liquid market in the world with an average daily turnover of $3.98 trillion.

Forex is a portmanteau of foreign currency and exchange. Foreign exchange is the process of changing one currency into another currency for a variety of reasons, usually for commerce, trading, or tourism. According to a recent triennial report from the Bank for International Settlements (a global bank for national central banks), the average was more than $5.1 trillion in daily forex trading volume.