Fixed Exchange Rates
There are two ways the price of a currency can be determined against another. A fixed, or pegged, rate is a rate the government (central bank) sets and maintains as the official exchange rate. A set price will be determined against a major world currency (usually the U.S. dollar, but also other major currencies such as the euro, the yen or a basket of currencies). In order to maintain the local exchange rate, the central bank buys and sells its own currency on the foreign exchange market in return for the currency to which it is pegged. (To learn more, read What Are Central Banks? and Get To Know The Major Central Banks.)

If, for example, it is determined that the value of a single unit of local currency is equal to US$3, the central bank will have to ensure that it can supply the market with those dollars. In order to maintain the rate, the central bank must keep a high level of foreign reserves. This is a reserved amount of foreign currency held by the central bank that it can use to release (or absorb) extra funds into (or out of) the market. This ensures an appropriate money supply, appropriate fluctuations in the market (inflation/deflation), and ultimately, the exchange rate. The central bank can also adjust the official exchange rate when necessary.

Floating Exchange Rates
Unlike the fixed rate, a floating exchange rate is determined by the private market through supply and demand. A floating rate is often termed “self-correcting”, as any differences in supply and demand will automatically be corrected in the market. Take a look at this simplified model: if demand for a currency is low, its value will decrease, thus making imported goods more expensive and stimulating demand for local goods and services. This in turn will generate more jobs, causing an auto-correction in the market. A floating exchange rate is constantly changing.

In reality, no currency is wholly fixed or floating. In a fixed regime, market pressures can also influence changes in the exchange rate. Sometimes, when a local currency does reflect its true value against its pegged currency, a “black market”, which is more reflective of actual supply and demand, may develop. A central bank will often then be forced to revalue or devalue the official rate so that the rate is in line with the unofficial one, thereby halting the activity of the black market.

In a floating regime, the central bank may also intervene when it is necessary to ensure stability and to avoid inflation; however, it is less often that the central bank of a floating regime will interfere.

Breaking A 24-Hour Market Into Manageable Trading Sessions
While a 24-hour market offers a considerable advantage for many institutional and individual traders because it guarantees liquidity and the opportunity to trade at any conceivable time, it also has its drawbacks. Although currencies can be traded any time, a trader can only monitor a position for so long. This means that there will be times of missed opportunities, or worse, when a jump in volatility will lead the spot to move against an established position when the trader isn’t around. To minimize this risk, a trader needs to be aware of when the market is typically volatile and decide what times are best for his or her strategy and trading style.