Currency trading, commonly known as forex trading, is the buying and selling of currency pairs in the foreign exchange market to earn profits through speculation. Presently, the currency market, or forex market, is one of the world's largest and most liquid markets. The primary factor that differentiates forex trading from other types of trading is its liquidity. The purchase and sale of one currency for another take place simultaneously. This kind of trading is also known as 'Speculative Forex Trading. If you have an online trading account, you don’t need any additional permission to do currency trading. You can buy and sell currency pairs on the NSE or the BSE currency segment. Currency trading is a 24-hour market that is only closed from Friday evening to Sunday evening, but the 24-hour trading sessions are misleading. There are three sessions that include the European, Asian, and trading sessions. Although there is some overlap in the sessions, the main currencies in each market are traded mostly during those market hours. This means that certain currency pairs will have more volume during certain sessions. Traders who stay with pairs based on the dollar will find the most volume in the U.S. All currency trading is done in pairs. Unlike the stock market, where you can buy or sell a single stock, you have to buy one currency and sell another currency in the forex market. Next, nearly all currencies are priced out to the fourth decimal point.