Investment Dictionary: Forex - FX

The foreign exchange (also known as "forex" or "FX") market is the place where currencies are traded. The overall forex market is the largest, most liquid market in the world with an average traded value that exceeds $1.9 trillion per day and includes all of the currencies in the world.

Investopedia Says:
There is no central marketplace for currency exchange, rather, trade is conducted over-the-counter. The forex market is open 24 hours a day, five days a week, with currencies being traded worldwide among the major financial centers of London, New York, Tokyo, Zürich, Frankfurt, Hong Kong, Singapore, Paris and Sydney - spanning most time zones.

The forex is the largest market in the world in terms of the total cash value traded, and any person, firm, or country may participate in this market.

Related Links: 
Learn how the largest and fastest growing market can work for you. The Forex Market
Find out how this tool magnifies both gains and losses. Forex Leverage: A Double-Edged Sword
Moving from equities to currencies requires you to adjust how you interpret quotes, margin, spreads and rollovers. A Primer On The Forex Market
Before entering this market, you should define what you need from your broker and from your strategy. Getting Started In Forex
We go over the ground rules and available resources needed for this undertaking. Wading Into The Currency Market
Learn the pros and cons of trading forex through these two types of brokers. Trading Through A Market Maker Vs. An ECN
Stocks are not the only securities underlying options--learn how to use FOREX options for profit and hedging. Getting Started In Forex Options
Here we go over a framework from which to build your own personalized but profitable strategy. Devising A Medium-Term Forex Trading System
Find out how these investments can diversify your portfolio. Venturing Into Non-Dollar Currencies