Any forex transaction that settles for a date later than spot is considered a "forward." The price is calculated by adjusting the spot rate to account for the difference in interest rates between the two currencies. The amount of adjustment is called "forward points." The forward points reflect only the interest rate differential between two markets. They are not a forecast of how the spot market will trade at a date in the future.
During the 15th century, the Medici family were required to open banks at foreign locations in order to exchange currencies to act on behalf of textile merchants. To facilitate trade, the bank created the nostro (from Italian, this translates to "ours") account book which contained two columned entries showing amounts of foreign and local currencies; information pertaining to the keeping of an account with a foreign bank. During the 17th (or 18th) century, Amsterdam maintained an active Forex market. In 1704, foreign exchange took place between agents acting in the interests of the Kingdom of England and the County of Holland.
Factors like interest rates, trade flows, tourism, economic strength, and geopolitical risk affect supply and demand for currencies, which creates daily volatility in the forex markets. An opportunity exists to profit from changes that may increase or reduce one currency's value compared to another. A forecast that one currency will weaken is essentially the same as assuming that the other currency in the pair will strengthen because currencies are traded as pairs.
The mere expectation or rumor of a central bank foreign exchange intervention might be enough to stabilize the currency. However, aggressive intervention might be used several times each year in countries with a dirty float currency regime. Central banks do not always achieve their objectives. The combined resources of the market can easily overwhelm any central bank. Several scenarios of this nature were seen in the 1992–93 European Exchange Rate Mechanism collapse, and in more recent times in Asia.
There are actually three ways that institutions, corporations and individuals trade forex: the spot market, the forwards market, and the futures market. Forex trading in the spot market has always been the largest market because it is the "underlying" real asset that the forwards and futures markets are based on. In the past, the futures market was the most popular venue for traders because it was available to individual investors for a longer period of time. However, with the advent of electronic trading and numerous forex brokers, the spot market has witnessed a huge surge in activity and now surpasses the futures market as the preferred trading market for individual investors and speculators. When people refer to the forex market, they usually are referring to the spot market. The forwards and futures markets tend to be more popular with companies that need to hedge their foreign exchange risks out to a specific date in the future.