Forex is the one financial market that never sleeps, meaning you can trade at all hours of the day (or night). Unlike the world's stock exchanges, which are located in physical trading rooms like the New York Stock Exchange or the London Stock Exchange, the Forex market is known as an 'Over-the-counter market' (or OTC). This means that the trades take place directly between the parties holding the currencies, rather than being managed via an exchange.
Investors – Investment firms who manage large portfolios for their clients use the Fx market to facilitate transactions in foreign securities. For example, an investment manager controlling an international equity portfolio needs to use the Forex market to purchase and sell several currency pairs in order to pay for foreign securities they want to purchase.
The foreign exchange market is where currencies are traded. Currencies are important to most people around the world, whether they realize it or not, because currencies need to be exchanged in order to conduct foreign trade and business. If you are living in the U.S. and want to buy cheese from France, either you or the company that you buy the cheese from has to pay the French for the cheese in euros (EUR). This means that the U.S. importer would have to exchange the equivalent value of U.S. dollars (USD) into euros. The same goes for traveling. A French tourist in Egypt can't pay in euros to see the pyramids because it's not the locally accepted currency. As such, the tourist has to exchange the euros for the local currency, in this case the Egyptian pound, at the current exchange rate.