How much each pip is worth is called the "pip value." For any pair where the USD is listed second, the above-mentioned pip values apply. If the USD is listed first, the pip value may be different. To find the pip value of the USD/CHF, for example, divide the normal pip value (mentioned above) by the current USD/CHF exchange rate. A micro lot is worth $0.10/0.9435 = $0.1060, where 0.9435 is the current price of the pair. For JPY pairs (USD/JPY), go through this same process, but then multiply by 100. For a more detailed explanation, see Calculating Pip Value in Different Forex Pairs.
Controversy about currency speculators and their effect on currency devaluations and national economies recurs regularly. Economists, such as Milton Friedman, have argued that speculators ultimately are a stabilizing influence on the market, and that stabilizing speculation performs the important function of providing a market for hedgers and transferring risk from those people who don't wish to bear it, to those who do. Other economists, such as Joseph Stiglitz, consider this argument to be based more on politics and a free market philosophy than on economics.
An investor can profit from the difference between two interest rates in two different economies by buying the currency with the higher interest rate and shorting the currency with the lower interest rate. Prior to the 2008 financial crisis, it was very common to short the Japanese yen (JPY) and buy British pounds (GBP) because the interest rate differential was very large. This strategy is sometimes referred to as a "carry trade."
The currency exchange rate is the rate at which one currency can be exchanged for another. It is always quoted in pairs like the EUR/USD (the Euro and the US Dollar). Exchange rates fluctuate based on economic factors like inflation, industrial production and geopolitical events. These factors will influence whether you buy or sell a currency pair.
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.