Forex, short for foreign exchange, is the global market for trading national currencies against one another. It is the largest financial market in the world, with a daily trading volume exceeding $7 trillion.  

Unlike stock markets, which have physical exchanges, forex operates as an over-the-counter (OTC) market, meaning transactions occur directly between parties via electronic networks. This market operates 24 hours a day, five days a week, starting in Sydney, followed by Tokyo, London, and New York, reflecting its truly global nature. 

The forex market enables participants to buy and sell currency pairs, such as EUR/USD or USD/JPY. Each pair consists of a base currency and a quote currency. For instance, in the EUR/USD pair, the EUR is the base currency and USD is the quote currency. A rise in the EUR/USD exchange rate indicates that the euro has strengthened against the dollar. 

Market participants include banks, financial institutions, governments, corporations, and individual traders.