In all cases, to make a meaningful description of trading hours worldwide, the opening and closing times at each location worldwide need to be presented with a common base reference time. In this article, for instance, the data is referenced to GMT. In other articles with a United States orientation, however, the common base reference time often used is Eastern Standard Time. It isn't wrong, but it's a little confusing for readers who don't distinguish between GMT and EST --something few persons other than forex traders and airline personnel need to deal with on a regular basis.
When you trade forex, you're effectively borrowing the first currency in the pair to buy or sell the second currency. With a US$5-trillion-a-day market, the liquidity is so deep that liquidity providers—the big banks, basically—allow you to trade with leverage. To trade with leverage, you simply set aside the required margin for your trade size. If you're trading 200:1 leverage, for example, you can trade £2,000 in the market while only setting aside £10 in margin in your trading account. For 50:1 leverage, the same trade size would still only require about £40 in margin. This gives you much more exposure, while keeping your capital investment down.
According to the 2018 Greenwich Associates study, Citigroup and JPMorgan Chase & Co. were the two biggest banks in the forex market, combining for more than 30 percent of the global market share. UBS, Deutsche Bank, and Goldman Sachs made up the remaining places in the top five. According to CLS, a settlement and processing group, the average daily trading volume in January 2018 was $1.805 trillion.
The modern foreign exchange market began forming during the 1970s. This followed three decades of government restrictions on foreign exchange transactions under the Bretton Woods system of monetary management, which set out the rules for commercial and financial relations among the world's major industrial states after World War II. Countries gradually switched to floating exchange rates from the previous exchange rate regime, which remained fixed per the Bretton Woods system.
The need to exchange currencies is the primary reason why the forex market is the largest, most liquid financial market in the world. It dwarfs other markets in size, even the stock market, with an average traded value of around U.S. $2,000 billion per day. (The total volume changes all the time, but as of August 2012, the Bank for International Settlements (BIS) reported that the forex market traded in excess of U.S. $4.9 trillion per day.)