Day Trading - What Is It? by Andy Hargreaves
Day trading usually follows one of two approaches, either beating the spread or attempting to catch short term trends. The spread is the difference between what is being offered for a stock (the bid) and the price being asked for the stock (the ask). With spread trading, you attempt to buy at the bid and sell at the ask as many times as possible. Spread traders can make hundreds of this type of trade every day.
ECNs or Electronic Communication Networks are a recent development. They are completely electronic exchanges with very low commissions and very fast execution of orders. As a method of encouraging traders to use their networks, some ECNs offer incentives in the form of a rebate. In some cases, this can allow a day trader to make money simply from buying and selling a stock at the same price.
Day trading can be very profitable if you get it right, but you need to research as much as possible and take advantage of the free simulation software that is available for you to practice with before you take the plunge. Remember, day trading is not for the faint hearted!