Forex is short for foreign exchange (FX), where currencies from all around the world are bought or sold among each other, known as forex trading. In simpler terms foreign exchange market is a global market also called the forex market, where one can buy a currency in exchange for another. For example, you can buy US dollars by selling your Euros or whatever currency you have in possession. The currencies of the world have differences in their prices if compared with each other and forex traders or investors trade these currencies to earn profit from these differences. They either buy one currency to sell it at a higher price later or sell a currency to buy it at a lower price later.