Day trading refers to the practice of buying and selling financial instruments within the same trading day such that all positions will usually (not necessarily always) be closed before the market close of the trading day. This is different from After-hours trading. Traders that participate in day trading are called day traders. Some of the more commonly day-traded financial instruments are stocks, stock options, currencies, and a host of futures contracts such as equity index futures, interest rate futures, and commodity futures. Day trading used to be the preserve of financial firms and professional investors and speculators. Many day traders are bank or investment firm employees working as specialists in equity investment and fund management. However, day trading has become increasingly popular among casual traders due to advances in technology, changes in legislation, and the popularity of the internet. Characteristics Trade Frequency Although collectively called day trading, there are many sub-trading styles within day trading. A day trader is actively searching for potential trading setups (a stock or any other financial instruments that, in the judgement of the day trader, is ready to move in price with a potential for a substantial profit. Depending on one's trading system (game), strategy, the number of trades the trader can make a day may vary from none to dozens. Some day traders focus on very short term trading within the trading day, in which a trade may last seconds to a few minutes. Day traders may buy and sell many times in a trading day and may receive trading fee discounts from the brokerage as a rusult, as a trading bonus. Some day traders focus only on price momentum, others on trend patterns, and still others on an unlimited number of strategies they feel are profitable. Winning day traders find they must learn to be more patient for the opportunity to ride on the strong move, that may arise at any moment. Day traders exit positions before the market closes to avoid any and all unmanageable risks - negtiveprice gaps (differences between the previous day's close and the next day's open price) at the open - overnight price movements against the position held. Day traders, like all traders, have their rules. Exiting before the close is their golden rule to be obeyed at all times. Other traders believe they should let the profits run, so it is acceptable to stay with a position after the market closes. - not for day traders. Once you get hit for a 10 to 20% overnight loss, your swing or investor trading life will likely be altered forever. Day traders often borrow money to trade. It's called margin trading. Since margin interests are typically only charged on overnight balances, there is no cost to the day trader for the margin benefit. Profit and Risks Because of the nature of financial leverage and the rapid returns that are possible, day trading can be either extremely profitable or extremely unprofitable, and high-risk profile traders can generate either huge percentage returns or huge percentage losses. Some day traders manage to earn millions per year solely by day trading. Because of the high profits (and losses) that day trading makes possible, these traders are sometimes portrayed as "bandits" or "gamblers" by other investors. Some individuals, however, make a consistent living day trading. Nevertheless day trading can become very risky, especially if any one of the following is present while trading: trading a loser's game/ system rather than a game that's at least winnable, trading with poor discipline (ignoring your own day trading strategy, tactics, rules), inadaquate risk capital with the accompanying excess stress of having to "survive", and/or incompetent money management (executing trades poorly). Above all, like a world-class athlete, say Tiger Woods in golf, a winning day trader, that is, a consistently profitable trader, would not think of conducting his or her business of trading without the guidance and support of a world-class consultant / coach - to attain and sustain day trading mastery and profitability.  The common use of buying on margin (using borrowed funds) amplifies gains and losses, such that substantial losses or gains can occur in a very short period of time. In addition, brokers usually allow bigger margins for daytraders. Where overnight margins required to hold a stock position are normally 50% of the stock's value, many brokers allow pattern day trader accounts to use levels as low as 25% for intraday purchases. This means a day trader with the legal minimum $25,000 in his account can buy $100,000 worth of stock during the day, as long as half of those positions are exited before the market close. Because of the high risk of margin use, and of other day trading practices, a day trader will often have to exit a losing position very quickly, in order to prevent a greater, unacceptable loss, or even a disastrous loss, much larger than his original investment, or even larger than his total assets. History Originally, the most important U.S. stocks were traded on the New York Stock Exchange. A trader would contact a stockbroker, who would relay the order to a specialist on the floor of the NYSE. These specialists would each make markets in only a handful of stocks. The specialist would match the purchaser with another broker's seller; write up physical tickets that, once processed, would effectively transfer the stock; and relay the information back to both brokers. Brokerage commissions were fixed at 1% of the amount of the trade, i.e. to purchase $10,000 worth of stock cost the buyer $100 in commissions. One of the first steps to make day trading of shares potentially profitable was the change in the commission scheme. In 1975, the United States Securities and Exchange Commission (SEC) made fixed commission rates illegal, giving rise to discount brokers offering much reduced commission rates. Financial Settlement Financial settlement periods used to be much longer: Before the early 1990s at the London Stock Exchange, for example, stock could be paid for up to 10 working days after it was bought, allowing traders to buy (or sell) shares at the beginning of a settlement period only to sell (or buy) them before the end of the period hoping for a rise (or fall) in price. This activity was identical to modern day trading, but for the longer duration of the settlement period. But today, to reduce market risk, the settlement period is typically three working days. Reducing the settlement period reduces the likelihood of default, but was impossible before the advent of electronic ownership transfer. Electronic Communication Networks The systems by which stocks are traded have also evolved, the second half of the twentieth century having seen the advent of Electronic Communication Networks (ECNs). These are essentially large proprietary computer networks on which brokers could list a certain amount of securities to sell at a certain price (the asking price or "ask") or offer to buy a certain amount of securities at a certain price (the "bid"). The first of these was Instinet. Instinet or "inet" (ECNs and exchanges are usually known to traders by a three- or four-letter designators, which identify the ECN or exchange on Level II stock screens) was founded in 1969 as a way for major institutions to bypass the increasingly cumbersome and expensive NYSE, also allowing them to trade during hours when the exchanges were closed. Early ECNs such as Instinet were very unfriendly to small investors, because they tended to give large institutions better prices than were available to the public. This resulted in a fragmented and sometimes illiquid market. The next important step in facilitating day trading was the founding in 1971 of NASDAQ -- a virtual stock exchange on which orders were transmitted electronically. Moving from paper share certificates and written share registers to "dematerialized" shares, computerized trading and registration required not only extensive changes to legislation but also the development of the necessary technology: online and real time systems rather than batch; electronic communications rather than the postal service, telex or the physical shipment of computer tapes, and the development of secure cryptographic algorithms. These developments heralded the appearance of "market makers": the NASDAQ equivalent of a NYSE specialist. A market maker has an inventory of stocks to buy and sell, and simultaneously offers to buy and sell the same stock. Obviously, it will offer to sell stock at a higher price than the price at which it offers to buy. This difference is known as the "spread". It is of no importance to the market-maker whether the price of a stock goes up or down, as it has enough stock and capital to constantly buy for less than it sells. Today there are about 500 firms who participate as market-makers on ECNs, each generally making a market in four to forty different stocks. Without any legal obligations, market-makers were free to offer smaller spreads on ECNs than on the NASDAQ. A small investor might have to pay a $0.25 spread (e.g. he might have to pay $10.50 to buy a share of stock but could only get $10.25 for selling it), while an institution would only pay a $0.05 spread (buying at $10.40 and selling at $10.35).